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1.
J Environ Manage ; 358: 120857, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38626485

RESUMO

Secondary alumina dross (SAD) has emerged as an alternative to bauxite in the production of flash setting admixtures (FSA), a critical admixture in shotcrete. However, the presence of hazardous components has hampered its large-scale adoption. This study conducted field tests at an FSA factory, utilizing SAD as the primary raw material, to evaluate the feasibility and environmental risks. The results confirmed that SAD can effectively replace bauxite in FSA production without compromising quality, as it closely resembled the chemical properties of bauxite. Emissions of fluorides, heavy metals, dioxins in flue gases during production met the relevant Chinese standards. The analysis of hazardous component distribution revealed that more than 50% of volatile components, such as Cl, Cd, Pb, and Zn, were directed into fly ash, exhibiting a significant internal accumulation pattern. In contrast, more than 95% of low-volatility components, including Cu, Cr, Mn, and F, were transferred to the FSA, and the introduction of CaCO3 was confirmed to effectively immobilize F. Moreover, the leaching risk of heavy metals and fluorides in FSA applications slightly increased but remained minimal and within acceptable limits. This technology provides an environmentally sound solution for the disposal of SAD.


Assuntos
Óxido de Alumínio , Metais Pesados , Óxido de Alumínio/química , Metais Pesados/análise
2.
Nanotechnology ; 35(9)2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38016442

RESUMO

Lithium-sulfur (Li-S) batteries have gained considerable attention for high theoretical specific capacity and energy density. However, their development is hampered by the poor electrical conductivity of sulfur and the shuttle of polysulfides. Herein, the acidified bamboo-structure carbon nanotubes (BCNTs) were mixed with polyvinylidene difluoride and pyrolyzed at high-temperature to obtain the fluorinated bamboo-structure carbon nanotubes (FBCNTs), which were compounded with sulfur as the cathode. The prepared S@FBCNTs with sulfur loading reaching 74.2 wt.% shows a high initial specific capacity of 1407.5 mAh·g-1at the discharge rate of 0.1 C. When the discharge rate was increased to 5 C, the capacity could be maintained at 622.3 mAh·g-1. The electrical conductivity of carbon nanotubes is effectively improved by semi-ionic C-F bonds formed by the doped F atoms and carbon atoms. Simultaneously, the surface of the F-containing carbon tubes exhibits strong polarity and strong chemisorption effect on polysulfides, which inhibits the shuttle effect of Li-S batteries.

3.
J Environ Manage ; 311: 114877, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35279489

RESUMO

The improper disposal of large amounts of solid waste (SW) has led to serious ecological and environmental problems, especially heavy metal (HM) pollution. Converter steelmaking has the potential to co-process SW, but the distribution of heavy metals (HMs) during converter steelmaking is unclear. In this study, the effects of smelting temperature and slag alkalinity on the distribution of typical HMs in the SW of steel samples, steel slag, and the gas phase were investigated in a specially-made induction furnace. The results showed that upon increasing the smelting temperature, As (As2S3) was mainly distributed in the steel sample, and the HM-containing compounds Cr2O3, CrCl3, ZnCl2, ZnS, ZnO, PbCl2, PbS, and PbO were mainly distributed in the gas phase. Upon increasing the alkalinity within a certain range, the distribution of HMs in steel samples and steel slag increased gradually, while their distribution in the gas phase decreased. Thermodynamic calculations, Eh-pH diagrams, XRD patterns, and XPS spectra indicated that impurity elements in the hot metal and the CaO content affected the chemical reactions by which HM-containing compounds in the steel sample formed elemental HMs and those in steel slag existed as oxides; therefore, it is necessary to choose a suitable temperature and alkalinity for slag when disposing of different types of SW.

4.
J Environ Manage ; 322: 116145, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36070648

RESUMO

Heavy metals (HMs) in mixed hazardous waste can be volatilized in the kiln for preparing sintered bricks, which greatly increases the environmental risk. In this study, the volatilization, transformation, and leaching of HMs from bricks were evaluated. Field tests and laboratory leaching experiments were carried out. HM-contaminated soil was used to prepare sintered bricks at high-temperature in a tunnel kiln. Release of HMs from brick under rainfall conditions was investigated in laboratory simulation experiments. The field tests showed that the total amount of Pb, Zn, Cd distributed to the gas phase were all less than 2%, but the amount of Hg entering the gas phase 40.1%-60.5% in the particulate forms. The As leaching rate increased after sintering of bricks in the kiln, which was attributed to the increased formation of soluble arsenate and the reduced availability of sorption sites. The tank leaching test indicated that the release mechanism of trance elements (Cr, As, Zn, Cd, Pb and Ni) was mainly controlled by diffusion. This study provides useful knowledge for decreasing the volatilization and leaching of HMs from sintered bricks prepared using hazardous waste.


Assuntos
Mercúrio , Metaloides , Metais Pesados , Arseniatos , Cádmio , Resíduos Perigosos , Chumbo , Metais Pesados/análise , Solo
5.
Chem Biodivers ; 18(5): e2001069, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33855794

RESUMO

Breast cancer is one of the most common cancer with high morbidity and mortality in women. This study aimed to explore the potential mechanism of costunolide inducing MCF-7 cells apoptosis by multi-spectroscopy, molecular docking, and cell experiments. The results manifested that costunolide interacted with calf thymus DNA (ct-DNA) in a spontaneous manner, and the minor groove as the preferential binding mode. Furthermore, costunolide inhibited cell proliferation and colony formation. Hoechst 33258 staining showed that cell apoptosis induced by costunolide might be related to DNA damage. The apoptosis mechanism relied on regulating the protein expression of Bax, Bcl-2, p53, Caspase-3 and the activation of p38MAPK and nuclear factor κB (NF-κB) pathways. This study will provide some experimental basis and potential therapeutic strategy for breast cancer treatment.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Simulação de Acoplamento Molecular , Sesquiterpenos/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Bovinos , Proliferação de Células/efeitos dos fármacos , DNA/química , DNA/efeitos dos fármacos , Dano ao DNA , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Células MCF-7 , Sesquiterpenos/química , Espectrofotometria Ultravioleta
6.
J Environ Manage ; 299: 113584, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34488106

RESUMO

A field test was conducted to study the emission and distribution characteristics of dioxins during co-processing of hazardous waste in a multicomponent slurry gasifier (MCSG). The toxicity equivalent concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in all exhaust gas, waste water, and solid waste under both blank condition (i.e., feedstock was normal coal-water slurry) and test condition (i.e., feedstock mixed with hazardous waste and labeling reagents) were analyzed. Results showed that organic matter was fully degraded in the MCSG. The dioxin amount in the black water flash steam increased with the addition of hazardous waste and chlorine in the feedstock, and octachlorodibenzo-p-dioxins (OCDD) with the largest increase is the most easily formed monomer in dioxins. The dioxin amount in all samples was far below the standard limit in China and other countries. This indicates the low environmental risk from dioxins during the co-processing process. The dioxin distribution trend in solid, liquid, and gas phase during co-processing did not change: 86.63%-94.18%, 0.02%-0.13%, and 5.8%-13.23% of PCDDs were distributed in the exhaust gas, waste water, and solid waste, respectively, while 6.10%-22.95%, 0.59%-0.80%, and 76.45%-93.10% of PCDFs were distributed in the exhaust gas, waste water, and solid waste, respectively.


Assuntos
Dioxinas , Dibenzofuranos Policlorados/análise , Monitoramento Ambiental , Resíduos Perigosos , Incineração , Resíduos Sólidos
7.
Chem Biodivers ; 17(11): e2000382, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32914574

RESUMO

Oxidative damage in cells induced by reactive oxygen species (ROS) is a main factor in diabetes mellitus diseases progression. The composition of anthocyanins from Padus racemosa (APR) and the protective effects of APR on H2 O2 -induced rat insulinoma (INS-1) cells damage and streptozocin (STZ)-induced diabetes mice were investigated in this study. The main components of APR were cyanidin-cyanidin glucosyl-rutinoside, cyanidin-cyanidin xylosyl-rutinoside, cyanidin-xylosyl-glucoside and cyanidin-rutinoside, which were determined by liquid chromatography-mass spectrometry (LC/MS). APR could scavenge the 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical and superoxide radical in vitro. ROS level was decreased and the cell viability was increased in INS-1 cells after treated with APR. Cell apoptosis induced by H2 O2 in INS-1 cells was decreased after incubation with APR. APR could decrease the phosphorylation of p38 and the nuclear translocation of p65, which indicated that APR could inhibit the activation of p38 Mitogen-activated protein kinase (MAPK) and Nuclear factor kappa B (NF-κB) cell signaling pathways. Meanwhile, APR could effectively reduce the blood glucose and blood lipid in STZ-induced diabetic mice. These results suggested that APR might be a potential agent for diabetes mellitus diseases treatment.


Assuntos
Antocianinas/química , Apoptose/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Substâncias Protetoras/química , Prunus/química , Animais , Antocianinas/isolamento & purificação , Antocianinas/farmacologia , Antocianinas/uso terapêutico , Antioxidantes/química , Glicemia/análise , Linhagem Celular Tumoral , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Frutas/química , Frutas/metabolismo , Camundongos , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Extratos Vegetais/química , Substâncias Protetoras/isolamento & purificação , Substâncias Protetoras/farmacologia , Substâncias Protetoras/uso terapêutico , Prunus/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
8.
Int J Syst Evol Microbiol ; 69(10): 3202-3206, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31339485

RESUMO

A Gram-stain-negative, rod-shaped and facultative anaerobic strain named YE-B6T was isolated from the intestine of abalone, Haliotis discus hannai. The reactions of oxidase and catalase were both positive. Strain YE-B6T could grow at 10-37 °C (optimum, 28-33 °C), at pH 7-9 (optimum, pH 7) and in salinity of 0-8 % NaCl (w/v; optimum, 2 %). The 16S rRNA gene sequence of strain YE-B6T had maximum sequence similarities to Cohaesibacter celericrescens H1304T (98.0 %), Cohaesibacter marisflavi DQHS21T (97.4 %), Cohaesibacter haloalkalitolerans JC131T (97.4 %) and Cohaesibacter gelatinilyticus CL-GR15T (97.3 %). Results of phylogenetic analysis showed that it was affiliated to the genus Cohaesibacter within the order Rhizobiales in the Alphaproteobacteria. The respiratory quinone of strain YE-B6T was Q-10. The cellular fatty acids mainly comprised C18 : 1 ω7c and summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c). The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylmonomethylethanolamine, two unidentified aminolipids, two unidentified polar lipids and one unidentified phospholipid. The G+C content of strain YE-B6T was 55.6 mol%. Based on its genotypic, physiological and biochemical characteristics, strain YE-B6T represented a novel species within the genus Cohaesibacter, for which the name Cohaesibacterintestini sp. nov. is proposed. The type strain of the new species is YE-B6T (=MCCC 1A13131T=KCTC 62716T).


Assuntos
Gastrópodes/microbiologia , Intestinos/microbiologia , Filogenia , Alphaproteobacteria/classificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
9.
Environ Pollut ; 356: 124260, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38815888

RESUMO

The advancement of co-processing solid wastes in coal-fired boilers is significant for waste recycling and contributes to the sustainable development of the coal-fired power industry. However, concerns over the emission of dioxins during co-processing have prompted a comprehensive investigation into the dioxin emission properties. In this study, the PCDD/F emission concentrations of seven coal-fired boilers, including three pulverized coal boilers and four circulating fluidized bed boilers were examined. The results indicate that co-processing solid wastes in coal-fired boilers did not lead to an increase in the mass concentration of dioxins in either the flue gas or solid samples, and the international toxic equivalents (I-TEQ) of dioxins in the flue gas complied with prevailing emission standards (0.1 ng I-TEQ/Nm3) in China, proving that coal-fired boilers co-processing would not raise the emission risk of dioxins. The types of waste during co-processing had minimal effect on the I-TEQ of dioxins. A significant proportion of PCDD/Fs was observed in the ash samples, while only 13.0-25.7% and 0.7-6.8% of dioxins were distributed in the boiler slag and the flue gas, respectively. The emission factor of dioxins under the blank conditions ranged from 0.009 to 0.327 ng I-TEQ/kg-coal, while it ranged from 0.015 to 0.129 ng I-TEQ/kg-(coal+waste) under the co-processing conditions. The reduction of emission factor under co-processing condition could be attributed to the significant decrease of dioxins I-TEQ.

10.
Microbiol Spectr ; : e0399022, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37754757

RESUMO

Although gut bacteria are vital to their hosts, few studies have focused on marine animals. Psychrilyobacter is frequently related to various marine animals, but its interaction with host remains unknown due to the lack of host-associated isolate or genomic information. Here, we combined cultivation-independent and cultivation-dependent methods to uncover the potential roles of Psychrilyobacter in the host abalone. The high-throughput sequencing and literature compiling results indicated that Psychrilyobacter is widely distributed in marine and terrestrial ecosystems with both host-associated and free-living lifestyles, but with a strong niche preference in the guts of marine invertebrates, especially abalone. By in vitro enrichment that mimicked the gut inner environment, the first host-related pure culture of Psychrilyobacter was isolated from the abalone intestine. Phylogenetic, physiological, and biochemical characterizations suggested that it represents a novel species named Psychrilyobacter haliotis B1. Carbohydrate utilization experiments and genomic evidence indicated that B1 can utilize diverse host-food-related monosaccharides and disaccharides but not polysaccharides, implying its potential role in the downstream fermentation instead of the upstream food degradation in the gut. Particularly, this strain showed potential to colonize the gut and benefit the host via different strategies, such as the short-chain fatty acids generation by fermenting peptides and/or amino acids, and the putative production of diverse vitamins and antibiotics to support the host growth and antipathogenicity. To our knowledge, strain B1 represents the first host-related pure culture of Psychrilyobacter; genomic and metabolic evidence showed some beneficial characteristics of the dominant gut anaerobe to the host. IMPORTANCE Psychrilyobacter is a globally distributed bacterial genus and with an inhabiting preference for guts of marine invertebrates. Due to the difficulty of cultivation and the limited genomic information, its role in host remains largely unknown. We isolated the first host-associated Psychrilyobacter species from abalone gut and uncovered its functional potential to the host through different mechanisms. Our findings provide some insights into the understanding of host-microbe interactions on a core taxon with the marine invertebrates, and the isolate may have an application potential in the protection of marine animals.

11.
Environ Sci Pollut Res Int ; 30(4): 10202-10212, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36071356

RESUMO

Field studies were conducted to study the emission and distribution characteristics of dioxins by elevating the chlorine concentration in feedstock in a circular fluidized bed boiler. The concentration and total equivalent quantity of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in all flue gas, electrostatic ash, bag filter ash, and bottom ash samples under blank condition (i.e., feedstock was normal coal) and chlorine labeling condition (i.e., feedstock mixed with coal and chlorine-containing labeling agent) were analyzed. Results illustrated that the concentration of PCDD/Fs in all gaseous and ash samples increased with the addition of chlorine in feedstock, with the largest and least increment in dioxin concentration observed in electrostatic ash and flue gas. PCDDs were the predominate congeners in flue gas, accounted for 50.1-60.4% of the total PCDD/F concentration under chlorine labeling and blank conditions, while PCDD/F distribution changed from PCDD- to PCDF-predominate by increasing chlorine content in feedstock under all field test conditions: 46.6-92.9%, 34.0-76.1%, and 47.0-53.1% of PCDFs were distributed in electrostatic ash, bag filter ash, and bottom ash, respectively. Highly chlorinated PCDD/F congeners such as O8CDD/F and 1,2,3,4,6,7,8-H7CDD/F were the primary contributors to dioxin concentration in flue gas and bottom ash samples, whereas low-chlorinated 2,3,7,8-T4CDF and 1,2,3,7,8-P5CDF congeners became critically dominating in electrostatic and bag filter ash.


Assuntos
Dioxinas , Dibenzodioxinas Policloradas , Cinza de Carvão/análise , Dibenzodioxinas Policloradas/análise , Cloro , Dibenzofuranos , Incineração , Dibenzofuranos Policlorados , Gases , Cloretos , Carvão Mineral
12.
Sci Total Environ ; 875: 162565, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36889396

RESUMO

Dioxin degradation is considered essential for the environmentally sound management of municipal solid waste incineration fly ash (MSWIFA). Among the many degradation techniques, thermal treatment has shown good prospects owing to its high efficiency and wide range of applications. Thermal treatment is divided into high-temperature thermal, microwave thermal, hydrothermal, and low-temperature thermal treatments. High-temperature sintering and melting not only have dioxin degradation rates higher than 95 % but also remove volatile heavy metals, although energy consumption is high. High-temperature industrial co-processing effectively solves the problem of energy consumption, but with a low fly ash (FA) mixture, and the process is limited by location. Microwave thermal treatment and hydrothermal treatment are still in the experimental stage and cannot be used for large-scale processing. The dioxin degradation rate of low-temperature thermal treatment can also be stabilized at higher than 95 %. Compared to other methods, low-temperature thermal treatment is less costly and energy consumption with no restriction on location. This review comprehensively compares the current status of the above-mentioned thermal treatment methods and their ability to dispose of MSWIFA, especially the potential for large-scale processing. Then, the respective characteristics, challenges, and application prospects of different thermal treatment methods were discussed. Finally, based on the goal of low carbon and emission reduction, three possible approaches for improvement were proposed to address the challenges of large-scale processing of low-temperature thermal treatment, namely, adding a catalyst, changing the FA fraction, or supplementing with blockers, providing a reasonable development direction for the degradation of dioxins in MSWIFA.

13.
J Hazard Mater ; 446: 130680, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36592557

RESUMO

Development of co-processing technology in the cement industry in China is important for environmentally sound disposal and recycling of waste, and contributes to sustainable development of the cement industry. However, dioxin pollution could negatively affect promotion of this technology. Therefore, it is necessary to study the emission characteristics of dioxins in cement kilns. In this study, the emission characteristics of dioxins and factors influencing their generation during co-processing solid wastes were studied in 14 new dry cement kilns. The dioxin concentrations were very similar regardless of whether solid wastes were fed into the kiln. In blank runs without co-processing, the average dioxin concentration was 0.0097 ng international toxic equivalents (I-TEQ)/Nm3. By comparison, that for co-processing solid wastes was 0.012 ng I-TEQ/Nm3. These values meet the relevant emission standards. The type of co-processed solid wastes had almost no effect on the dioxin concentration. At larger production scales, the concentration of dioxin emitted in the flue gas decreased. The dioxin concentrations in kiln dust were obviously higher than those in clinker and raw materials. The average emission factor of dioxin per ton of cement was 30 ng I-TEQ/t, which is equivalent to that in cement kilns in other countries.

14.
Waste Manag ; 168: 45-53, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37276633

RESUMO

Dioxins in municipal solid waste incineration fly ash (MSWIFA) can cause significant risks to the environment and human health. In this study, the low-temperature thermal treatment of MSWIFA under industrial conditions was simulated in the laboratory to investigate the process parameters for dioxin degradation and ash discharge stages. Correlation analysis and dioxin fingerprint characterization were used to analyze the degradation and ash discharge processes. The degradation efficiency of low-temperature thermal treatment was influenced by multiple factors. At 400℃ for 90 min and 1% O2, the dioxin removal rate was 95.80%, the detoxification rate was 91.73%, and the residual dioxin toxicity in MSWIFA was 22.7 ± 17.8 ng I-TEQ/kg, which was in line with the limit value of 50 ng I-TEQ/kg in the "Technical specification for pollution control of fly-ash from municipal solid waste incineration" (HJ1134-2020). The increase in dioxins during ash discharge did not follow a linear relationship with the process parameters. This was assumed to be related to the MSWIFA composition, as some components containing P, Si, and Al at 150 °C may inhibit dioxin formation. The dioxin increased only by 0.79 ± 2.65 ng/kg, an increase in toxicity of 0.42 ± 0.10 ng I-TEQ/kg, when treated at 150 °C for 30 min and 10% O2.


Assuntos
Dioxinas , Dibenzodioxinas Policloradas , Humanos , Incineração , Resíduos Sólidos , Cinza de Carvão , Temperatura , Dibenzodioxinas Policloradas/análise
15.
Front Microbiol ; 14: 1252127, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38075907

RESUMO

Introduction: Burkholderia is a rod-shaped aerobic Gram-negative bacteria with considerable genetic and metabolic diversity, which can beused for bioremediation and production applications, and has great biotechnology potential. However, there are few studies on the heavy metal resistance of the Burkholderia genus. Methods: In this paper, the distribution, characteristics and evolution of heavy metal resistance genes in Burkholderia and the gene island of Tn7-like transposable element associated with heavy metal resistance genes in Burkholderia were studied by comparative genomic method based on the characteristics of heavy metal resistance. Results and discussion: The classification status of some species of the Burkholderia genus was improved, and it was found that Burkholderia dabaoshanensis and Burkholderia novacaledonica do not belong to the Burkholderia genus.Secondly, comparative genomics studies and pan-genome analysis found that the core genome of Burkholderia has alarger proportion of heavy metal resistance genes and a greater variety of heavy metalresistance genes than the subsidiary genome and strain specific genes. Heavy metal resistance genes are mostly distributed in the genome in the form of various gene clusters (for example, mer clusters, ars clusters, czc/cusABC clusters). At the same time, transposase, recombinase, integrase and other genes were foundupstream and downstream of heavy metal gene clusters, indicating that heavy metal resistance genes may beobtained through horizontal transfer. The analysis of natural selection pressure of heavy metal resistance genes showed that heavy metal resistance genes experienced strong purification selection under purification selection pressure in the genome.The Tn7 like transposable element of Burkholderia was associated with the heavy metal resistance gene island, and there were a large number of Tn7 transposable element insertion events in genomes. At the same time, BGI metal gene islands related to heavy metal resistance genes of Tn7 like transposable element were found, and these gene islands were only distributed in Burkholderia cepacia, Burkholderia polyvora, and Burkholderia contaminant.

16.
ACS Omega ; 8(46): 43978-43992, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38027379

RESUMO

In recent years, the oil and gas reserves discovered in shallow water deltas in China have continued to grow. The research on shallow water delta deposition models and depositional genesis is becoming more and more mature. In this latest discovery, a unique type of extremely narrow channel shallow water delta deposit was found at the top of the V oil group in the lower part of the Minghuazhen Formation during the Neogene period at DL-A Oilfield, located in the Bohai Bay Basin. The width of most single channels in this deposit measures between 100 and 200m, which is relatively rare and differs from existing research. To better understand this unique narrow channel shallow water delta deposit, a range of analysis methods were conducted including trace element analysis, major element analysis, grain size analysis, core observation, casting thin section observation, 3D seismic analysis, and other methods. These analyses were used to determine the sedimentary environment and sedimentary genesis of the deposit in the study area. The results show the following: (1) The top of the V oil group in the lower part of Minghuazhen Formation was deposited with a strong oxidizing environment. In the early stage, the climate was dry and cold, and gradually changed to warm and humid in the late stage. (2) Due to the frequent exposure to the surface, obvious weathered surfaces and sedimentary discontinuities were observed on the cores; the particle size analysis shows that the lamina types developed in the study area are clastic-clay laminae and clay-clastic laminae, which are mostly developed in shallow lakes area. (3) Observations of cores and thin sections also indicated that the hydrodynamic conditions frequently changed in the study area, alternating between strong and weak hydrodynamic conditions in a short period due to the alternating occurrence of flood and dry periods during the rainy season. Weak hydrodynamic conditions and slow water flow result in insufficient undercutting and sidecutting of rivers. The alternating occurrence of flood periods and dry periods has led to the development of crevasse splays and frequent river channel diversions, resulting in the inability of long-term stable development of the river channel. Besides, the change of water level has also led to the rebuilding of the river. Therefore, the multiple effects led to the formation of an extremely narrow channel shallow water delta. The accuracy of the sedimentary model is verified by a comparative study of the Shaliu River and Buha River in the modern Qinghai Lake. The new extremely narrow channels deposition model proposed this time further improves the deposition theory. At the same time, the modern depositional characteristics of the Shaliu River and Buha River also reveal the reservoir deposition between channels that cannot be distinguished by seismic data, providing guidance for the development of oil and gas in the study area.

17.
Waste Manag ; 126: 133-140, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33752154

RESUMO

Persistent organic pollutants in soil are not readily degraded in the short term. The utilization of co-processing solid waste in cement kilns has received increasing attention in recent years. Co-processing may be a good way of disposing of dichlorodiphenyltrichloroethane-contaminated soil (CS). The feasibility of co-processing CS pretreated to desorb dichlorodiphenyltrichloroethane, was assessed by performing an industrial-scale trial, focusing on the risks posed by emissions to the environment. Samples of the input and output in cement kiln were collected for determining clinker quality, production operation, pollutant emissions, cement kiln system destruction efficiency, and distribution profiles of persistent organic pollutants unintentionally produced from kiln. The destruction efficiency and destruction removal efficiency both were > 99.99% in cement kiln system at the appropriate CS feeding rate. Emissions of stack gases produced by cement kilns co-processing CS were within the reasonable range set in China. Dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and polychlorinated biphenyls (PCBs) concentrations and distribution profiles in flue gases and particulate samples from two tests showed PCBs mainly formed at the same sites as PCDD/Fs, indicating they are may formed in a similar way in cement kiln. A comparison with the processing parameters in the clinker, cement kiln dust, and flue gas under baseline and co-processing conditions, manifested that co-processing had no effect on the operation or cement quality of the cement kiln. Thus co-processing CS at a rate of 20 t/h with pretreatment process, is an environmentally sound and highly efficient treatment for CS.


Assuntos
Poluentes Atmosféricos , Dibenzodioxinas Policloradas , China , Dibenzofuranos , Dibenzofuranos Policlorados/análise , Monitoramento Ambiental , Dibenzodioxinas Policloradas/análise , Solo
18.
J Biomed Nanotechnol ; 17(9): 1806-1811, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34688325

RESUMO

Lactate dehydrogenase (LDH) is one of key enzymes in glucose metabolism pathway, which plays a critical role in cell metabolism. Inhibition of LDH can inhibit glycolysis process, thereby inhibiting the occurrence and development of tumor cells. Two kinds of LDH inhibitors, apigenin and emodin, were obtained by testing the IC50 of several natural products in LDH enzyme reaction. The IC50 of apigenin was about 1/3 of LDH inhibitor sodium oxalate. A new method to evaluate the performance of LDH inhibitors based on CdTe QDs was established at the same time, which provides a new idea for research on LDH enzyme inhibitors.


Assuntos
Compostos de Cádmio , Pontos Quânticos , Apigenina/farmacologia , Fluorescência , L-Lactato Desidrogenase , Telúrio
19.
Pathol Res Pract ; 216(7): 152962, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32534699

RESUMO

BACKGROUND: Cyclin-dependent kinase 12 (CDK12) belongs to the cyclin-dependent kinase (CDK) family, modulating multiple cellular functions including DNA damage response (DDR), development and cellular differentiation, transcription, mRNA processing, splicing and pre-mRNA processing. CDK12 has been reported as both tumor suppressor and oncogene in various kinds of tumor. The function of CDK12 in gastric cancer (GC) remains unclear. METHODS/RESULTS: CDK12 mRNA expression was decreased in GC compared with non-tumor tissue based on GEO database. Also, low mRNA expression of CDK12 was detected in GC cell lines by qPCR. Similarly, CDK12 protein expression was also reduced in GC tissues compared with adjacent non-tumor tissues in 177 GC patients as shown by immunohistochemistry. Low expression of CDK12 was associated with organ metastasis, poorly differentiated adenocarcinoma and advanced stage. Consistent with human protein atlas database analysis, Low expression of CDK12 was correlated with worse overall survival (P < 0.001). Multivariate Cox regression indicated that low expression of CDK12 was an independent prognostic factor for GC patients (P < 0.001). Finally, a gene set enrichment analysis was performed to detect underlying internal mechanisms and biological processes. CONCLUSIONS: CDK12 is down-regulated in GC and its expression is negatively correlated with advanced stage, poorly differentiated adenocarcinoma and poor outcomes. Our findings suggest that CDK12 may be a potential tumor suppressor in GC.


Assuntos
Adenocarcinoma/patologia , Biomarcadores Tumorais/metabolismo , Quinases Ciclina-Dependentes/biossíntese , Neoplasias Gástricas/patologia , Adulto , Idoso , Biomarcadores Tumorais/análise , Regulação para Baixo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico
20.
Medicine (Baltimore) ; 99(1): e18371, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31895771

RESUMO

INTRODUCTION: Kawasaki disease (KD) is an acute vasculitis syndrome that mainly affects children and is the first cause of acquired heart disease. Coronary artery lesion is the most serious complication of KD. Only two previous studies have reported similar cases, but we reported patient was younger and had a longer follow-up. PATIENT CONCERNS: We reported a case of coronary sequelae of KD treated with rotational atherectomy and drug coated balloon (DCB). During the week after surgery, the patient complained of a slight chest pain intermittently, but no longer appeared after that. DIAGNOSIS: We diagnosed by electrocardiogram and angiography. Angiography showed that the anterior descending branch (LAD) proximal stenosis was 95%, the right coronary artery (RCA) middle stenosis was 99%, and the calcification was severe. INTERVENTIONS: We treat the patient with rotational atherectomy using a 1.25 mm burr, pre-dilatation of the stenosis lesion with a 3.5 mm × 15 mm non-compliant balloon was achieved. Then 3.5 mm × 15 mm drug eluting balloon was inflated at 10 atm for 60 seconds. OUTCOMES: After the 6-month follow-up (from October 2018 to March 2019), the symptom of angina disappeared. Coronary angiography 6 months later showed no apparent progression of vessel narrowing. CONCLUSION: The present case suggests that rotational atherectomy followed by DCB dilation could be an alternative revascularization therapy of choice in coronary KD sequelae complicated with atherosclerosis.


Assuntos
Aterectomia Coronária/métodos , Aneurisma Coronário/cirurgia , Síndrome de Linfonodos Mucocutâneos/complicações , Adulto , Angioplastia Coronária com Balão/métodos , Calcinose/patologia , Aneurisma Coronário/diagnóstico por imagem , Aneurisma Coronário/etiologia , Vasos Coronários/patologia , Eletrocardiografia , Humanos , Masculino
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