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1.
Environ Res ; 248: 118420, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38316384

RESUMO

The hydrophobic nature of an extractant is particularly critical in the treatment of wastewater. Considering that dicationic ionic liquids (DILs) are likely to be more hydrophobic, a comparative study of the separation of phenol from waters using [NTf2]- based monocationic ionic liquids (MILs) and DILs is carried out both from experimental and theoretical analysis perspectives. Experimental results revealed that DILs exhibited superior extraction ability compared to MILs, with extraction efficiencies of 93.7% and 97.4% using [BMIM][NTf2] and [C6(MIM)2][NTf2]2 as extractants, respectively. The microscopic examination through theoretical calculations elucidated the higher hydrophobicity and extraction efficiency of DILs over MILs. The results indicated that the DIL showed stronger hydrophobicity than the MIL because the hydrogen bond strength between the DIL and water was lower than that of the MIL. Although the hydrogen bond strength between the DIL and phenol was lower than that of the MIL, the stronger van der Waals forces existed between DIL and phenol, so DIL was more efficient in extracting phenol. In addition, the experimental parameters were optimized to provide basic data for application, such as mass ratio of ILs to water, extraction time and temperature, pH, and initial phenol content. Finally, the DILs were recovered using rotary evaporation apparatus, and the results demonstrated that DILs had good recovery and reuse performance. In brief, this work could provide an effective method for the treatment of phenol-containing wastewater. And the revelation of molecular mechanism is expected to positively impact the design of high-performance task-specific ILs.


Assuntos
Líquidos Iônicos , Líquidos Iônicos/química , Fenol , Águas Residuárias , Fenóis , Água/química , Interações Hidrofóbicas e Hidrofílicas
2.
Artigo em Inglês | MEDLINE | ID: mdl-38401080

RESUMO

Objective: This study aimed to analyze the difference between non-ligation and traditional ligation techniques for papillary thyroid micro-carcinoma (PTMC) patients. Methods: Patients undergoing thyroidectomy in the Department of General Surgery, Ruijin Hospital, affiliated with Shanghai Jiao Tong University, Lu Wan Branch, were retrospectively enrolled. The gender, age, operation method, operation duration, tumor size, size of thyroidectomy specimen, postoperative bleeding, drainage volume on the first postoperative day, preoperative and postoperative levels of parathyroid hormone (PTH), and blood calcium were collected. Results: Compared with the traditional ligation technique, the non-ligation technique significantly shortened the operation time (69.36 ± 1.38 vs. 82.72 ± 2.12, P < .0001) and reached less variation of the serum calcium (2.32 ± 0.01 vs 2.28 ± 0.01, P < .001) and PTH (26.58 ± 0.08 vs 22.01 ± 1.04, P < .05) on the first postoperative day, and the above biochemical indicators returned to normal 3 weeks after surgery. The PTH in the No-ligation technique group was 7.20± 1.99, which was significantly lower than that in the Traditional ligation group (20.78± 3.78) (P < .01). Conclusion: No-ligation technique can significantly reduce the operation time in thyroidectomy but may temporarily affect the levels of parathyroid hormone and blood calcium, and the above changes returned to normal 3 weeks after surgery. These results highlighted that No-ligation technique can benefit patients and will be a favorable treatment method.

3.
ChemSusChem ; 17(9): e202301774, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38197219

RESUMO

The recovery of valuable metals from spent lithium-ion batteries using deep eutectic solvents (DESs) is an environmentally and economically beneficial process. In this study, a method has been developed for recovering LiNi0.33Co0.33Mn0.33O2. Our process operates under mild conditions and with a little oxalic acid as a reducing agent, dissolving lithium, cobalt, manganese, and nickel completely utilizing a DES that is composed of tetrabutylammonium chloride and of monochloroacetic acid. Lithium and nickel were selectively precipitated using oxalic acid. Cobalt and manganese were precipitated as oxalates by adding an oxalic acid aqueous solution. Finally, the DES can be regenerated by evaporating the water. Importantly, valuable metals can be recovered with a 100 % yield through the process of DES recycling. This environmentally friendly and recyclable process is suitable for the recycling of spent lithium-ion batteries industry.

4.
Endocr Connect ; 13(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37947264

RESUMO

Objective: The aim was to explore the effects of preoperative calcium and activated vitamin D3 supplementation on post-thyroidectomy hypocalcemia and hypo-parathyroid hormone-emia (hypo-PTHemia). Methods: A total of 209 patients were randomly divided into control group (CG) and experimental group (EG). Oral calcium and activated vitamin D3 supplementation were preoperatively administered to EG, whereas a placebo was administered to CG. Data on serum calcium, phosphorus, and PTH concentrations before operation, on postoperative day 1 (POPD1), at postoperative week 3 (POPW3), and on the length of postoperative hospitalization were collected. Results: The serum calcium, phosphorus, and PTH concentrations, as well as the incidence of postoperative hypocalcemia and hypo-PTHemia, did not significantly differ between EG and CG. Subgroup analysis revealed that the serum calcium concentrations of the experimental bilateral thyroidectomy subgroup (eBTS) on POPD1 and POPW3 were higher than that of the control bilateral thyroidectomy subgroup (cBTS) (P < 0.05); the reduction of serum calcium in eBTS on POPD1 and POPW3 was less than those in cBTS (P < 0.05). However, significant differences were not observed between the unilateral thyroidectomy subgroups (UTS) (P > 0.05). Moreover, the incidence of postoperative hypocalcemia in cBTS on POPD1 was significantly higher than that in eBTS (65.9% vs 41.7%) (P < 0.05). The length of hospitalization in cBTS (3.55 ± 1.89 days) was significantly longer than that (2.79 ± 1.15 days) in eBTS (P < 0.05). Conclusion: Short-term preoperative prophylactic oral calcium and activated vitamin D3 supplementation could effectively reduce the incidence of postoperative hypocalcemia and decrease the length of postoperative hospitalization in patients who have undergone bilateral thyroidectomy.

5.
Front Neurol ; 14: 1292804, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38116114

RESUMO

Objective: To investigate the clinical efficacy of percutaneous microballoon compression in the treatment of recurrent TN. Methods: This retrospective study included 33 patients who underwent percutaneous microballoon compression for the treatment of recurrent TN from March 2019 to May 2022. Postoperative pain recurrence and facial numbness were assessed according to the Barrow Neurological Institute (BNI) pain score. Patients' anxiety and sleep status during follow-up were assessed according to the Self-rating Anxiety Scale (SAS) and Pittsburgh Sleep Quality Index (PSQI). Results: All patients (33 cases) were followed up for 12-38 months, with an average follow-up time of 23 months. On postoperative day 1, 31 patients (93.9%) reported no pain, and 2 patients were given drug treatment for pain relief, The total efficacy was 93.9%. Moreover, 2 patients (6.1%) reported significant pain relief 2 weeks postoperatively. There are many complications during and after PBC. The incidence of the trigeminocardiac reflex (TCR) during surgery was 100%, and the incidence of facial numbness, masseter muscle weakness, labial herpes and headache was 97, 60.6, 12.1 and 3%. No patient experienced severe facial numbness, hearing impairment, diplopia, injury to cranial nerves, Meningitis, intracranial haemorrhage or keratitis. 1 patient had recurrence of pain at 6 months post-op, which was relieved by oral medication. 81.8% suffered from anxiety and 54.5% had poor sleep quality before surgery. After the period of PBC, SAS and PSQI scores decreased continuously. There were significant improvements in anxiety and sleep status postoperatively compared with preoperatively. Conclusion: PBC is a safe and effective option for the treatment of recurrent TN. The arduous and demanding nature of the clinical course subjects the patient to severe pain, mental, and physical stress. Thankfully, it significantly improves the symptoms of anxiety, depression, and sleep quality.

6.
BMC Musculoskelet Disord ; 24(1): 864, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37936087

RESUMO

BACKGROUND: The clinical treatment of long bone defets in the extremities caused by trauma, infection, tumours, and nonunion has been a challenge for orthopaedic surgeons. Bone transport techniques have become the only way to treat such bone defects. However, inevitable difficulties and complications related to bone transport techniques have been reported in many studies. AIM: The purpose of this study was to investigate the risk factors for complications and the effectiveness of the Ilizarov bone transport technique in the treatment of tibial bone defects. METHODS: The study was conducted in 199 patients who underwent treatment with the Ilizarov bone transport technique at our institution from May 2012 to September 2019. Patient demographic data, complications and clinical outcomes after a minimum of 2 years of follow-up were collected and retrospectively analysed. Additionally, a risk factor analysis was performed for the top three major complications. The clinical outcomes were evaluated using the Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria at the last clinical follow-up. RESULTS: A total of 199 patients underwent follow-up for 12-40 months, with an average of 23.5 months, and all achieved bone healing. A total of 310 complications occurred, with an average of 1.04 minor complications and 0.48 major complications per patient. The top three complications were pin tract infection in 48 cases (61.3%), axial deviation in 86 cases (43.2%), and delayed union in 50 cases (25.13%). Multivariate analysis showed that the bone defect length (P = 0.02, OR = 5.489), the number of previous surgeries (P = 0.003, OR = 2.204), and the external fixation index (P = 0.01, OR = 1.202) were significantly correlated with pin tract infection. Bone defects of the middle 1/3 (P < 0.001, OR = 23.769), the bone defect length (P < 0.001, OR = 2.776), and the external fixation index (P < 0.001, OR = 1.154) were significantly correlated with axial deviation. The bone defect length (P = 0.003, OR = 1.242), soft tissue defects (P = 0.013, OR = 0.312) and bone defects of the distal 1/3 (P = 0.023, OR = 4.257) were significantly correlated with delayed healing. The ASAMI bone score at the last follow-up showed a rate of excellent and good bone results of 95.48% and a rate of excellent functional results of 87.94%. CONCLUSION: The Ilizarov bone transfer technique is an effective method for treating tibial bone defects, and shortening the treatment period can reduce the incidence of complications. Older patients and those with longer bone defects, a higher external fixation index, more previous operations, and defects of the middle and distal 1/3 had a higher incidence of complications.


Assuntos
Técnica de Ilizarov , Fraturas da Tíbia , Humanos , Estudos Retrospectivos , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/cirurgia , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Tíbia/patologia , Técnica de Ilizarov/efeitos adversos , Cicatrização , Resultado do Tratamento , Fixadores Externos
7.
J Orthop Surg Res ; 18(1): 889, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993906

RESUMO

BACKGROUND: Treating long bone defects of the extremities caused by trauma, infection, tumours, and nonunion has been challenging for clinical orthopaedic surgeons. Bone transport techniques have the potential to treat bone defects. However, inevitable docking site complications related to bone transport techniques have been reported in many studies. The purpose of this study was to investigate the risk factors associated with docking site complications in patients who underwent the Ilizarov bone transport technique for the treatment of tibial bone defects. METHODS: This retrospective study included 103 patients who underwent bone transport for the treatment of large bone defects in the tibia from October 2012 to October 2019. Patient demographic data, complications and clinical outcomes after a minimum of 2 years of follow-up were collected and retrospectively analysed. Additionally, univariate analysis and logistic regression analysis were used to analyse the factors that may affect the development of docking site complications in patients with tibial bone defects treated with the Ilizarov bone transport technique. The clinical outcomes were evaluated using the Association for the Study and Application of the Ilizarov criteria (ASAMI) at the last clinical follow-up. RESULTS: All 103 patients with an average follow-up of 27.5 months. The docking site complications rate per patient was 0.53, and delayed union occurred in 22 cases (21.4%), axial deviation occurred in 19 cases (18.4%) and soft tissue incarceration occurred in 10 cases (9.7%). According to the results of the logistic regression analysis, the bone defect length (P = 0.001, OR = 1.976), and bone defect of distal 1/3 (P = 0.01, OR = 1.976) were significantly correlated with delayed union. Bone defect length (P < 0.001, OR = 1.981) and external fixation time (P = 0.012, OR = 1.017) were significantly correlated with axial deviation. Soft tissue defects (P = 0.047, OR = 6.766) and the number of previous operations (P = 0.001, OR = 2.920) were significantly correlated with soft tissue incarceration. The ASAMI bone score at the last follow-up showed a rate of excellent and good bone results of 95.1% and a rate of excellent functional results of 90.3%. CONCLUSION: The Ilizarov bone transport technique is a practical and effective method for the treatment of tibial bone defects. However, the incidence of complications at the docking site is high, of which bone defect length, external fixation time, the number of previous operations, soft tissue defects and the bone defect of distal 1/3 are statistically significantly associated with the occurrence of docking site complications.


Assuntos
Técnica de Ilizarov , Fraturas da Tíbia , Humanos , Tíbia/cirurgia , Tíbia/lesões , Estudos Retrospectivos , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/cirurgia , Fraturas da Tíbia/etiologia , Técnica de Ilizarov/efeitos adversos , Resultado do Tratamento , Fixadores Externos
8.
Environ Res ; 229: 115897, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37054839

RESUMO

Indole is an essential signal molecule in microbial studies. However, its ecological role in biological wastewater treatments remains enigmatic. This study explores the links between indole and complex microbial communities using sequencing batch reactors exposed to 0, 15, and 150 mg/L indole concentrations. A concentration of 150 mg/L indole enriched indole degrader Burkholderiales, while pathogens, such as Giardia, Plasmodium, and Besnoitia were inhibited at 15 mg/L indole concentration. At the same time, indole reduced the abundance of predicted genes in the "signaling transduction mechanisms" pathway via the Non-supervised Orthologous Groups distributions analysis. Indole significantly decreased the concentration of homoserine lactones, especially C14-HSL. Furthermore, the quorum-sensing signaling acceptors containing LuxR, the dCACHE domain, and RpfC showed negative distributions with indole and indole oxygenase genes. Signaling acceptors' potential origins were mainly Burkholderiales, Actinobacteria, and Xanthomonadales. Meanwhile, concentrated indole (150 mg/L) increased the total abundance of antibiotic resistance genes by 3.52 folds, especially on aminoglycoside, multidrug, tetracycline, and sulfonamide. Based on Spearman's correlation analysis, the homoserine lactone degradation genes which were significantly impacted by indole negatively correlated with the antibiotic resistance gene abundance. This study brings new insights into the effect of indole signaling on in biological wastewater treatment plants.


Assuntos
Microbiota , Percepção de Quorum , Percepção de Quorum/fisiologia , Resistência Microbiana a Medicamentos , Lactonas/farmacologia , Antibacterianos/farmacologia , Indóis/farmacologia
9.
Water Res ; 235: 119814, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36934538

RESUMO

Quorum sensing (QS) has attracted great attention due to its important role in the bacterial interactions and its relevance to water management. With the development of high-throughput sequencing technology, a specific database for QS-related sequence annotation is urgently needed. Here, Hidden Markov Model (HMM) profiles for 38 types of QS-related proteins were built using a total of 4024 collected seed sequences. Based on both homolog search and keywords confirmation against the non-redundant database, we established a QS-related protein (QSP) database, that includes 809,721 protein sequences and 186,133 nucleotide sequences, downloaded available at: https://github.com/chunxiao-dcx/QSP. The entries were classified into 38 types and 315 subtypes among 91 bacterial phyla. Furthermore, an automatic annotation pipeline, named QSAP, was developed for rapid annotation, classification and abundance quantification of QSP-like sequences from sequencing data. This pipeline provided the two homolog alignment strategies offered by Diamond (Blastp) or HMMER (Hmmscan), as well as a data cleansing function for a subset or union set of the hits. The pipeline was tested using 14 metagenomic samples from various water environments, including activated sludge, deep-sea sediments, estuary water, and reservoir water. The QSAP pipeline is freely available for academic use in the code repository at: https://github.com/chunxiao-dcx/QSAP. The establishment of this database and pipeline, provides a useful tool for QS-related sequence annotation in a wide range of projects, and will increase our understanding of QS communication in aquatic environments.


Assuntos
Bactérias , Percepção de Quorum , Bactérias/genética , Proteínas , Esgotos/microbiologia , Água
10.
Ying Yong Sheng Tai Xue Bao ; 34(12): 3271-3278, 2023 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-38511366

RESUMO

Normalized difference vegetation index (NDVI) is an important indicator reflecting vegetation cover and growth status. It is of significance for regional ecological conservation and natural resource management to investigate its spatial and temporal variation trends and response to ecological factors. We divided Liaoning Province into three ecological geographical regions, including northwest agro-pastoral zone, central agricultural zone, and eastern agroforestry zone. Based on remote sensing, vegetation, climate, topography and human activities, we used trend analysis and geographic probe model to examine the spatial and temporal trends of NDVI in Liaoning Province, and analyzed the intensity and interaction mechanism of each driver on the spatial distribution pattern of NDVI. The results showed that the annual average NDVI in Liaoning Province from 2001 to 2020 was 0-0.92, showing a distribution pattern of high in the east and low in the west, high in the inland and low in the coastal land. The overall trend of vegetation cover was increasing, and the NDVI increasing areas were mainly concentrated in the northwest agro-pastoral zone and the eastern agroforestry zone, the NDVI reduction areas were mainly concentrated at the border between the central agricultural zone and the eastern agroforestry zone, as well as in the coastal area of the eastern agroforestry zone. The annual average NDVI change varied among the three ecological-geographic zones. The NDVI of the northwest agro-pastoral zone from 2001 to 2020 were generally low, but showed a fluctuating trend of slow increase. The NDVI of the eastern agroforestry zone was high overall, and the interannual variation of NDVI was generally stable. The distribution of high and low NDVI in the central agricultural zone was staggered, and the interannual variation of NDVI showed a decreasing trend. Natural factors were the key drivers of NDVI changes in the three ecogeographic zones, with cumulative temperature and precipitation having the greatest influence. The interactions between the factors were all mutually and nonlinearly enhanced.


Assuntos
Clima , Ecossistema , Humanos , Temperatura , Agricultura , Mudança Climática , China
11.
ACS Omega ; 7(22): 18861-18869, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35694518

RESUMO

Lignin is a natural aromatic compound in plants. Several lignin structural models have been proposed in the past years, but all the models cannot be converted to benzene carboxylic acids (BCAs) for all aromatic rings connected to oxygen. This inspired us to explore the structures of lignin. Based on the yields of BCAs, the results of 13C NMR and ethanolysis residues, and gas chromatography-mass spectrometry and electrospray ionization mass spectrometry of ethanolysis of lignin, we have constructed a structural model of lignin with a formula C6407H6736O2590N147S3. The model not only satisfies the results of analyses, but also explains the generation of BCAs from lignin oxidation and the ethanolysis products. Importantly, double-ring and triple-ring aromatic clusters are found in lignin, and some of them are connected by alkyl bridges, which results in conventional low conversions of lignin. Our findings in the structures of lignin may significantly influence the structures and applications of lignin.

12.
Pestic Biochem Physiol ; 184: 105114, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35715053

RESUMO

Previously, deltamethrin (a Type-II pyrethroid) has been reported to increase triglyceride (fat) accumulation in adipocytes, while its underlying molecular mechanism is not fully determined. The aim of this study was to further investigate the molecular mechanisms of deltamethrin induced fat accumulation in murine 3T3-L1 adipocytes. Consistent to previous reports, deltamethrin (10 µM) significantly promoted adipogenesis in 3T3-L1 adipocytes. RNA sequencing (RNA-seq) results showed that 721 differentially expressed genes (DEGs) were identified after deltamethrin treatment, involving in 58 Functional groups of Gene Ontology (GO) and 255 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Several key functional groups regulating adipogenesis, such as fat cell differentiation (Igf1, Snai2, Fgf10, and Enpp1) and cytosolic calcium ion concentration (Nos1, Cxcl1, and Ngf) were significantly enriched. Collectively, these results suggest that the promotion of adipogenesis by deltamethrin was attributed to an obesogenic global transcriptomic response, which provides further understanding of the underlying mechanisms of deltamethrin-induced fat accumulation.


Assuntos
Adipócitos , Piretrinas , Células 3T3-L1 , Adipogenia/genética , Animais , Perfilação da Expressão Gênica , Camundongos , Nitrilas , Piretrinas/metabolismo , Piretrinas/toxicidade
13.
ACS Omega ; 7(12): 10413-10419, 2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35382329

RESUMO

The absorption of SO2 from flue gas and its conversion to chemicals is important in the industry. Functional ionic liquids (ILs) have been broadly used to absorb SO2 in flue gas, but seldom convert it to chemicals. As we know, water is inevitable in a desulfurization process. In this work, three functional ILs (monoethanolaminium lactate-[MEA][Lac], 1,1,3,3-tetramethylguanidinium lactate-[TMG][Lac], tetraethylammonium lactate-[N2222][Lac]) with or without water were used as absorbents to absorb SO2 in flue gas, and then the absorbed SO2 in the absorbents was converted to sulfur via a Claus reaction. The result shows that the three ILs can efficiently absorb SO2 and convert it to sulfur. But the addition of water in the ILs can reduce the conversion of absorbed SO2, and the conversion increases with increasing the acidity of absorbents. To explain this phenomenon, we studied the Claus reaction in H2SO3, NaHSO3 and Na2SO3 aqueous solutions. It turns out that the conversion of the Claus reaction is related to the species of S (IV) in the order of the oxidability: H2SO3 > HSO3 - > SO3 2-, and their proportions dependent on the pH of solutions. On the basis of the absorption mechanism of SO2 in functional ILs aqueous solution, H2S reacts with HSO3 - and SO3 2- with weaker oxidability, resulting in the lower conversion. Importantly, we found that the addition of lactic acid could increase the conversion of SO2 via the Claus reaction.

14.
Environ Res ; 207: 112660, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-34995547

RESUMO

Indole and phenol often coexist in the coking wastewater, while the effects of phenol on microbial communities of indole metabolism were less explored. In this study, the microbial interactions within activated sludge microbial communities stimulated by indole (group A) or by indole and phenol (group B) were systematically investigated in sequencing batch reactors (SBRs). The results showed that the removal of indole was increased by adding phenol. By using high-throughput sequencing technology, it was found that α-diversity was reduced in both groups. According to the relative abundance analysis, the indole-degrading genus Comamonas was the core genus in both groups (33.94% and 61.40%). But another indole-degrading genus Pseudomonas was only enriched in group A with 12.22% relative abundance. Meanwhile, common aromatic degrading genus Dyella and Thermomonas were enriched only in group B. It was found that the relative abundance of cytochrome P450 and styrene degradation enzymes were increased in group B by PICRUSt analysis. Based on the phylogenetic molecular ecological networks (pMENs), module hub OTU_1149 (Burkholderia) was only detected in group B, and the positive interactions between the key functional genus Burkholderia and other bacteria were increased. This study provides new insights into our understanding of indole metabolism communities stimulated by phenol, which would provide useful information for practical coking wastewater treatment.


Assuntos
Microbiota , Esgotos , Reatores Biológicos , Indóis/metabolismo , Indóis/farmacologia , Fenol , Fenóis , Filogenia , Esgotos/microbiologia , Águas Residuárias
15.
J Agric Food Chem ; 69(41): 12148-12155, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34623140

RESUMO

It is generally considered that lignin is a three-dimensional amorphous polymer consisting of methoxylated phenylpropane structures. However, high yields of monomer structural units of lignin cannot be obtained through various ways, which inspired us to gain insights into the structures of lignin. Herein, enzymatic lignin (EL) was directly characterized by a solid-state 13C nuclear magnetic resonance spectrometer and Fourier transform infrared spectrometer and then subjected to ruthenium ion-catalyzed oxidation. According to the spectral characterization, it can be inferred that multi-ring aromatic clusters exist in EL because of the aromatic bridgehead carbon ratio of 0.136. Based on the results of ruthenium ion-catalyzed oxidation of the EL, it can be deduced that (1) double- and triple-aromatic ring clusters exist in the EL besides the traditional phenylpropane single-aromatic ring clusters, and (2) some aromatic rings with long-alkyl chain substituents exist in the EL, which is quite different from the traditional cognition of lignin. This investigation provides a new insight into the structure of EL.


Assuntos
Lignina , Rutênio , Catálise , Lignina/metabolismo , Espectroscopia de Ressonância Magnética , Oxirredução
16.
ACS Omega ; 5(12): 6809-6816, 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32258916

RESUMO

CO2 emission from flue gas is an important issue threatening human survival. Deep eutectic solvents (DESs), which have many unique properties, have been studied for CO2 capture. However, water can be absorbed by DESs during the absorption of CO2, which may increase the energy cost during the desorption of CO2. In this work, a new kind of hydrophobic functional DES formed by polyamine hydrochloride and thymol was synthesized and used for CO2 capture. It had been found that these DESs could efficiently capture CO2 even at low partial pressures. The CO2 capacity of [TEPA]Cl-thymol (n [TEPA]Cl/n thymol = 1:3) was high up to 1.355 mol CO2/mol DES at 40 °C and 101.3 kPa. Interestingly, these DESs were still hydrophobic after saturated with CO2. The CO2 absorption capacity increased with a decrease of temperature and an increase of CO2 partial pressure. Regeneration results showed that no obvious loss in the capacity could be found after five absorption/desorption cycles of these DESs. The Fourier transform infrared (FT-IR) spectra indicated that CO2 could interact with amino in the DESs by the formation of carboxylate. Moreover, the equilibrium constant and Henry's law constant in chemical absorption and physical absorption were studied.

17.
Front Oncol ; 10: 611809, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33520722

RESUMO

OBJECTIVES: There are few reports about the survival rate of patients with pancreatic adenosquamous cancer (PASC). This study evaluated and analyzed prognostic factors of patients with resectable pancreatic adenosquamous cancer (rPASC), which might fulfill the blank in the research of PASC. METHODS: In this study, we identified and analyzed 55 patients who were diagnosed with rPASC from January 2013 to May 2019 at the Pancreatic Disease Center of the Shanghai Ruijin Hospital affiliated with Shanghai Jiaotong University School of Medicine. Age, sex, BMI, tumor position, and other important demographic data were collected and analyzed. The follow-up was updated by December 31th, 2019 with a median follow-up of nine months. RESULTS: Among the 55 patients, 23 (41.8%) patients were female, and the mean age was 62.0 ± 10.3 years. The median overall survival (OS) time was 10 ± 2.1 months, and the median disease-free survival (DFS) time was 4 ± 0.9 months. The 1-year, 3-year, and 5-year survival rates were 40.9, 17.5, and 11.6%, respectively. The multivariate analysis showed that normal serum level of Ca199 (HR = 0.464, 95% CI = 0.222-0.970, P = 0.041) and Ca125 (HR = 0.441, 95% CI = 0.233-0.835, P = 0.012) were independent favorable prognostic factors. CONCLUSION: Patients with rPASC had poor survival. The 5-year survival rate was only 11.6%. Normal serum levels of Ca199 and Ca125 were independent favorable prognostic factors that predicted prognosis.

18.
R Soc Open Sci ; 5(5): 171523, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29892356

RESUMO

The selective hydrogenation of isophorone (3,5,5-trimethyl-2- cyclohexen-1-one) to produce 3,3,5-trimethylcyclohexanone (TMCH), an important organic solvent and pharmaceutical intermediate, is of significance in industry. However, the over-hydrogenation to produce the by-product 3,3,5-trimethylcyclohexanol causes issues. Up to now, it is still a challenge to hydrogenate isophorone to TMCH with high selectivity. In this work, we found that Lewis acids could inhibit the hydrogenation of C=O bond on isophorone, thus greatly improving the selectivity towards TMCH. In addition, added solvents like supercritical CO2 also had a positive impact on the selectivity. Both the conversion and selectivity could be increased to more than 99% when suitable Lewis acid and solvent were employed. Nevertheless, Lewis acid also exhibited some inhibition on the hydrogenation of the C=C bond of isophorone. Hence, a relatively weak Lewis acid, ZnCl2, is suitable for the selective hydrogenation.

19.
Phys Chem Chem Phys ; 20(26): 17942-17951, 2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29926044

RESUMO

Vanadium(v)-catalyzed aerobic oxidation in aqueous solution shows high selectivity in the field of C-C bond cleavage of carbohydrates for chemicals with less carbon atoms. However, the pathway of C-C bond cleavage from carbohydrates and the conversion mechanism are unclear. In this work, we studied the pathway and the mechanism of d-glucose oxidation to formic acid (FA) in NaVO3-H2SO4 aqueous solution using isotope-labeled glucoses as substrates. d-Glucose is first transformed to FA and d-arabinose via C1-C2 bond cleavage. d-Arabinose undergoes similar C1-C2 bond cleavage to form FA and the corresponding d-erythrose, which can be further degraded by C1-C2 bond cleavage. Dimerization and aldol condensation between carbohydrates can also proceed to make the reaction a much more complicated mixture. However, the fundamental reaction, C1-C2 bond cleavage, can drive all the intermediates to form the common product FA. Based on the detected intermediates, isotope-labelling experiments, the kinetic isotope effect study and kinetic analysis, this mechanism is proposed. d-Glucose first reacts with a vanadium(v) species to form a five-membered-ring complex. Then, electron transfer occurs and the C1-C2 bond weakens, followed by C1-C2 bond cleavage (with no C-H bond cleavage), to generate the H3COO˙-vanadium(iv) complex and d-arabinose. FA is generated from H3COO˙ that is oxidized by another vanadium(v) species. The reduced vanadium species is oxidized by O2 to regenerate to its oxidation state. This finding will provide a deeper insight into the process of C-C bond cleavage of carbohydrates for chemical synthesis and provide guidance for screening and synthesizing new highly-efficient catalyst systems for FA production.

20.
ACS Omega ; 3(11): 14910-14917, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31458156

RESUMO

The conversion of abundant renewable cellulose into versatile formic acid (FA) is a potential process for efficient energy storage and application. Vanadium(V)-catalyzed oxidation with O2 in acidic aqueous media now is the most common method to realize the FA production from cellulose with both high yields and high purity. However, vanadium-based catalysts are difficult to synthesize and expensive. Thus, the seeking for cheaper catalysts with the same high efficiency is expected. In this work, after testing a variety of metal salts in acidic aqueous solution for the conversion of cellulose under O2, iron(III) was found as a cheaper and readily available catalyst for FA formation, with a comparable yield (51.2%, based on carbon) with that of vanadium(V). The effect of reaction parameters was studied. The competition between oxidation and hydrolysis was found and discussed in detail. FeCl3 and H2SO4 can accelerate oxidation and hydrolysis, respectively, whereas suppress the other. The effects can reflect on the product distribution. Intermediates were found and the pathway from cellulose to products was reasonably proposed. The reusability of the catalytic system shows good performance after four runs. The mechanism study suggests a catalytic ability by a mutual transformation between iron(III) and iron(II), where iron(III) oxidizes substrates to iron(II) that is reoxidized by O2.

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