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Pendimethalin (PM) is an organic pollutant (herbicide), and systematic studies on PM degradation are scarce. The efficient degradation of PM in water remains a challenge that requires to be addressed. Herein, for the first time, elemental Co was doped into HKUST-1 using a solvothermal method to generate Co3O4/CuO@C via pyrolysis. The as-prepared catalyst was used to activate peroxymonosulfate (PMS) for PM degradation, obtaining a PM degradation efficiency of 98.2 % after 30 min. The assessment of the effects of various factors on the degradation efficiency revealed that 1O2 dominated PM degradation, whereas the contribution of SO4â¢- was negligible. Although 3Co3O4/CuO@C exhibited a good degradation performance against other organic pollutants, its degradation performance in real water was poor. The carbon layer reduced metal-ion leaching (Co and Cu), and the synergistic interactions between Co3O4 and CuO promoted PMS activation. The roles of the components of 3Co3O4/CuO@C in PM degradation by activated PMS were investigated in the presence of CoIV and Co-OOSO3-. Two possible PM degradation pathways were systematically proposed, and the toxicity of the intermediates was analyzed. Finally, a mechanism for PM degradation by 3Co3O4/CuO@C-activated PMS was proposed.
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BACKGROUND: Thrombosis with thrombocytopenia syndrome (TTS) is a very rare prothrombotic disorder that is a safety concern for some COVID-19 vaccines. We aimed to devise a case definition to estimate the incidence of thrombosis with thrombocytopenia as a proxy for TTS in a national insurance claims database. METHODS: We conducted a retrospective observational study using the National Health Insurance Research Database (NHIRD) in Taiwan over the three-year period prior to the SARS-COV-2 pandemic (2017-2019). Our case definition was all patients with newly diagnosed thrombosis co-occurring with a diagnosis of thrombocytopenia within seven days before or after the thrombosis diagnosis. Cases were identified using International Classification of Disease-10 codes. FINDINGS: We identified 2010 patients with newly diagnosed thrombosis co-occurring with thrombocytopenia during the study period. The mean age was 64.71 years; female:male ratio 1:1.45. The most frequent thrombotic events were coronary artery disease (18.81%), cerebral infarction (16.87%), and disseminated intravascular coagulation (13.13%). Cerebral venous sinus thrombosis was rare (<0.1%). The average annual incidence rate of co-occurring new diagnoses of thrombosis and thrombocytopenia was 2.84 per 100 000 population. Incidence rates were higher in men than women, except in 20-39 year-olds (higher in females). 20.6% of patients died within the first month after diagnosis. INTERPRETATION: We observed that the demographic and clinical characteristics of thrombosis with co-occurring thrombocytopenia using our case definition is different from that of TTS. Further research is needed to refine the case definition of TTS in the post-COVID-19 vaccination period.
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COVID-19 , Trombocitopenia , Trombosis , Humanos , Femenino , Masculino , Persona de Mediana Edad , COVID-19/complicaciones , COVID-19/epidemiología , Trombocitopenia/epidemiología , Trombocitopenia/complicaciones , Incidencia , Trombosis/epidemiología , Trombosis/etiología , Trombosis/complicaciones , Anciano , Estudios Retrospectivos , Taiwán/epidemiología , Adulto , SARS-CoV-2/aislamiento & purificación , Adulto Joven , Anciano de 80 o más Años , Bases de Datos Factuales , Adolescente , PandemiasRESUMEN
Pollutant treatment, hazardous solid waste conversion, and biomass resource utilization are significant topics in environmental pollution control, and simultaneously achieving them is challenging. Herein, we developed a "from waste absorbent to effective photocatalyst" upcycle strategy for nontoxic conversion of Cd(II) adsorbed on thiolation@wood-aerogel (TWA) into CdS/g-C3N4 heterojunctions through the in situ chemical deposition high-temperature carbonization combined conversion method to overcome the above problems simultaneously. We used Schiff base reaction to graft l-cysteine into dialdehyde@wood-aerogel to prepare TWA with a high Cd(II) adsorption capacity (600 mg/L, 294.66 mg/g). Subsequently, the spent Cd(II)-loaded-TWA was used as a substrate for in situ construction of Cd(II) into CdS/g-C3N4 heterojunction for activating peroxymonosulfate (PMS) under simulated sunlight [simulated solar light (SSL)], achieving efficient tetracycline (TC) degradation (20 mg/L, 95.32%). The Langmuir and pseudo-second-order models indicate single-layer chemical adsorption of Cd(II) on the TWA adsorption process. In the PMS/SSL system, CdS/g-C3N4@TWA efficiently and rapidly degraded TC via an adsorption-photocatalytic synergistic degradation mechanism. The used CdS/g-C3N4@TWA has a good biocompatibility. This study proposed design and preparation of a new type of wood aerogel absorbent and provided a novel upcycling strategy for innovative use of the spent waste adsorbent.
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The dazzling adsorbent products make people overlook the harm of heavy metals adsorbed on them. Hazardous waste adsorbents cause secondary pollution. In this study, waste lignocellulose was dissolved by alkaline urea solvent and high-intensity ultrasound, then cross-linked by epichlorohydrin to make hydrogel, which was utilized to adsorb toxic heavy-metal wastewater. In situ deposition and high-temperature carbonization turn the gel that has absorbed heavy metals into carbon aerogel-loaded metal oxide energy storage materials that may be employed as anodes in lithium-ion batteries with excellent electrochemical performance. The best reversible capacity was 435.86 mAh g-1 after 100 cycles at 0.2C, indicating that the hazardous solid waste generated by the removal of heavy metals using biomass-based adsorbent has potential lithium battery applications. Thus, we provide a fresh perspective on the efficient recycling of heavy metals as well as an environmentally friendly, high-value conservation strategy for lowering the danger of heavy-metal hazardous wastes.
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Efficient enzymatic hydrolysis is required for the production of high concentration monosaccharides and ethanol. The lignin and acetyl group in poplar can limit the enzymatic hydrolysis. However, the effect of delignification combined with deacetylation on the saccharification of poplar for high concentration monosaccharides was not clear. Herein, hydrogen peroxide-acetic acid (HPAA) was used for delignification and sodium hydroxide was used for deacetylation to enhance the hydrolyzability of poplar. Delignification with 60% HPAA at 80 °C could remove 81.9% lignin. Acetyl group was completely removed with 0.5% NaOH at 60 °C. After the saccharification, 318.1 g/L monosaccharides were obtained with a poplar loading of 35% (w/v). After simultaneous saccharification and fermentation, 114.9 g/L bioethanol was gained from delignified and deacetylated poplar. Those results showed the highest monosaccharides and ethanol concentrations in reported research. This developed strategy with a relatively low temperature could effectively improve the production of high concentration monosaccharide and ethanol from poplar.
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Lignina , Populus , Monosacáridos , Etanol , Madera , Fermentación , Ácido Acético , Hidrólisis , Peróxido de HidrógenoRESUMEN
Photocatalytic CO2 reduction is a promising technology for reaching the aim of "carbon peaking and carbon neutrality", and it is crucial to design efficient photocatalysts with a rational surface and interface tailoring. Considering that amine modification on the surface of the photocatalyst could offer a favorable impact on the adsorption and activation of CO2, in this work, amine-modified brookite TiO2 nanorods (NH2-B-TiO2) coupled with CuxS (NH2-B-TiO2-CuxS) were effectively fabricated via a facile refluxing method. The formation of a p-n junction at the interface between the NH2-B-TiO2 and the CuxS could facilitate the separation and transfer of photogenerated carriers. Consequently, under light irradiation for 4 h, when the CuxS content is 16%, the maximum performance for conversion of CO2 to CH4 reaches at a rate of 3.34 µmol g-1 h-1 in the NH2-B-TiO2-CuxS composite, which is approximately 4 times greater than that of pure NH2-B-TiO2. It is hoped that this work could deliver an approach to construct an amine-enriched p-n junction for efficient CO2 photoreduction.
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Alzheimer's disease (AD) is a progressive neurological condition. The rising prevalence of AD necessitates the rapid development of efficient therapy options. Despite substantial study, only a few medications are capable of delaying the disease. Several substances with pharmacological activity, derived from plants, have been shown to have positive benefits for the treatment of AD by targeting various enzymes, such as acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), ß-secretase, γ-secretase, and monoamine oxidases (MAOs), which are discussed as potential targets. Medicinal plants have already contributed a number of lead molecules to medicine development, with many of them currently undergoing clinical trials. A variety of medicinal plants have been shown to diminish the degenerative symptoms associated with AD, either in their raw form or as isolated compounds. The aim of this review was to provide a brief summary of AD and its current therapies, followed by a discussion of the natural compounds examined as therapeutic agents and the processes underlying the positive effects, particularly the management of AD.
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Enfermedad de Alzheimer , Plantas Medicinales , Acetilcolinesterasa/uso terapéutico , Enfermedad de Alzheimer/tratamiento farmacológico , Butirilcolinesterasa/uso terapéutico , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/uso terapéuticoRESUMEN
Zeolitic imidazolate framework-8 (ZIF-8) was evenly loaded on the surface of TiO2 doped with KI, using a solvent synthesis method, in order to produce a ZIF-8@TiO2 (KI) adsorption photocatalyst with good adsorption and photocatalytic properties. The samples were characterized by XRD, SEM, EDX, XPS, BET and UV-Vis. The photocatalytic efficiency of the material was obtained by photocatalytic tests. The results indicate that the doping with I inhibited the grain growth and reduced the crystallite size of TiO2, reduced the band gap width and improved the utilization rate for light. TiO2 (KI) was a single crystal of anatase titanium dioxide. The combination of ZIF-8 and TiO2 (KI) improved the specific surface area and increased the reaction site. The ZIF-8@TiO2 (KI) for Congo red was investigated to validate its photocatalytic performance. The optimal concentration of Congo red solution was 30 mg/L, and the amount of catalyst was proportional to the degradation efficiency. The degradation efficiency of ZIF-8@TiO2 (5%KI) was 76.42%, after being recycled four times.
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A novel Mg(II) metal-organic framework (Mg-MOF) was synthesized based on the ligand of 2,2'-bipyridine-4,4'-dicarboxylic acid. Single-crystal X-ray structural analysis confirmed that three-dimensional-nanostructure Mg-MOFs formed a monoclinic system with a channel size of 15.733 Å × 23.736 Å. N2 adsorption isotherm, Fourier transform infrared spectroscopy, thermogravimetric analysis and high-resolution transmission electron microscopy were performed to characterize the thermal stability and purity of the Mg-MOFs. The adsorption studies on four typical volatile organic compounds (VOCs) emitted during wood drying showed that Mg-MOFs have noteworthy adsorption capacities, especially for benzene and ß-pinene with adsorptions of 182.26 mg g-1 and 144.42 mg g-1, respectively. In addition, the adsorption of Mg-MOFs mainly occurred via natural adsorption, specifically, multi-layer physical adsorption, accompanied by chemical forces, which occurred in the pores where the VOCs molecules combined with active sites. As an adsorbent, Mg-MOFs exhibit versatile behaviour for toxic gas accumulation.
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A new and devastating disease, rapid ohia death (ROD), in Hawaii led to a state quarantine that regulates interisland transport of ohia wood and plant material to prevent spread of the causal pathogens. Heat treatments of ohia logs in commercial trade were considered for phytosanitary treatment. Vacuum steam (VS) was evaluated for its ability to eradicate the pathogens, Ceratocystis lukuohia and C. huliohia, in main stem logs from ROD-affected forest trees. Replicate loads of three debarked logs (24 to 43 cm in diameter, 1.7 to 2.0 m long) were VS treated at 56°C for 30 min (five loads) or 60°C for 60 min (four loads) at a sapwood depth equal to 70% of log radius. Percentage isolation of Ceratocystis from VS and ambient temperature logs before treatment and summarized by source tree ranged from 12 to 66% and 6 to 31% based on carrot baiting assays of tissue taken from outer and inner sapwood, respectively. No viable Ceratocystis was detected in sapwood locations for the 60°C/60 min schedule or inner locations for the 56°C/30 min schedule after treatment. Only one subsample (0.48%, n = 208) of the latter schedule treatment yielded Ceratocystis. Time needed for treatment ranged from 7.4 to 15 h for the 56°C/30 min schedule and from 8.6 to 19.2 h for the 60°C/60 min schedule. These results demonstrate that VS is an effective and efficient method for treating large-diameter ohia logs that mill owners and regulatory plant pathologists may consider for use in Hawaii.
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Myrtaceae , Vapor , Ceratocystis , VacioRESUMEN
Lignocellulose (LCE) was ultrasonically treated and intercalated into magnesium aluminum silicate (MOT) clay to prepare a nano-lignocellulose magnesium aluminum silicate polymer gel (nano-LCE-MOT) for the removal of Zn (II) from aqueous solution. The product was characterised using nitrogen adsorption/desorption isotherm measurements, Fourier-transform infrared spectroscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. The conditions for the adsorption of Zn (II) on nano-LCE-MOT were screened, and adsorption kinetics and isotherm model analysis were carried out to explore the adsorption mechanism and achieve the optimal adsorption of Zn (II). Optimal adsorption was achieved at an initial Zn (II) concentration of 800 mg/L at 60 °C in 160 min at a pH of 4.52. The adsorption kinetics were explored using a pseudo-second-order model, with the isotherm adsorption equilibrium found to conform to the Langmuir model. The maximum adsorption capacity of the nano-LCE-MOT polymer gel toward Zn (II) is 513.48 mg/g. The materials with adsorbed Zn (II) were desorbed using different media, with HCl found to be the most ideal medium to desorb Zn (II). The optimal desorption of Zn (II) was achieved in 0.08 mol/L HCl solution at 65 °C in 60 min. Under these conditions, Zn (II) was almost completely desorbed from the adsorbents, with the adsorption effect after cycling being slightly different from that of the initial adsorption.
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Zeolitic imidazolate framework-8 (ZIF-8) was doped with a rare-earth metal, Eu, using a solvent synthesis method evenly on the surface of a mixed-crystal TiO2(Mc-TiO2) structure in order to produce a core-shell structure composite ZIF-8(Eu)@Mc-TiO2 adsorption photocatalyst with good adsorption and photocatalytic properties. The characterisation of ZIF-8(Eu)@Mc-TiO2 was performed via X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller analysis (BET) and ultraviolet-visible light differential reflectance spectroscopy (UV-DRs). The results indicated that Eu-doped ZIF-8 was formed evenly on the Mc-TiO2 surface, a core-shell structure formed and the light-response range was enhanced greatly. The ZIF-8(Eu)@Mc-TiO2 for basic fuchsin was investigated to validate its photocatalytic performance. The effect of the Eu doping amount, basic fuchsin concentration and photocatalyst dosage on the photocatalytic efficiency were investigated. The results revealed that, when 5%-Eu-doped ZIF-8(Eu)@Mc-TiO2 (20 mg) was combined with 30 mg/L basic fuchsin (100 mL) under UV irradiation for 1 h, the photocatalytic efficiency could reach 99%. Further, it exhibited a good recycling performance. Thus, it shows certain advantages in its degradation rate and repeatability compared with previously reported materials. All of these factors suggested that, in an aqueous medium, ZIF-8(Eu)@Mc-TiO2 is an eco-friendly, sustainable and efficient material for the photocatalytic degradation of basic fuchsin.
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Logs of high-value eastern black walnut (Juglans nigra L.) are commonly exported from the United States for production of veneer and lumber. Veneer logs are not debarked to minimize degradation of wood quality and reduce moisture loss. Thousand cankers disease (TCD) is caused by the walnut twig beetle (Pityophthorus juglandis Blackman) and the fungal pathogen, Geosmithia morbida M. Kolarik, E. Freeland, C. Utley and N. Tisserat sp. nov., which colonize the inner bark of Juglans species. Effective eradication of these organisms by heat or chemical fumigation treatment is required for walnut logs prior to export. Because vacuum steam is an effective and efficient means of heating round wood, its use in eliminating the TCD causal agents was evaluated using Juglans logs (12- to 44-cm small end diameter and 1.7- to 1.9-m length) from TCD-symptomatic trees in Oregon and Washington State. Five replicate trials with three logs per load were conducted in a portable vacuum chamber to test two treatment schedules: 60°C for 60 min and 56°C for 30 min. Complete elimination of P. juglandis and G. morbida was achieved when using a minimum of 56°C at 5-cm targeted depth from bottom of bark furrow into the sapwood and held for 30 min. Treatment cycle time ranged from 298 to 576 min depending on log diameter and initial log temperature. Artificial inoculation of J. nigra trees with G. morbida within the TCD range in Pennsylvania was minimally successful in producing adequately colonized logs for experimental trials.
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Juglans , Animales , Hypocreales , Oregon , Pennsylvania , Enfermedades de las Plantas , Vapor , Resultado del Tratamiento , Árboles , Vacio , WashingtónRESUMEN
Thiol-lignocellulose sodium bentonite (TLSB) nanocomposites can effectively remove heavy metals from aqueous solutions. TLSB was formed by using -SH group-modified lignocellulose as a raw material, which was intercalated into the interlayers of hierarchical sodium bentonite. Characterization of TLSB was then performed with BET, FTIR, XRD, TGA, PZC, SEM, and TEM analyses. The results indicated that thiol-lignocellulose molecules may have different influences on the physicochemical properties of sodium bentonite, and an intercalated-exfoliated structure was successfully formed. The TLSB nanocomposite was subsequently investigated to validate its adsorption and desorption capacities for the zinc subgroup ions Zn(II), Cd(II) and Hg(II). The optimum adsorption parameters were determined based on the TLSB nanocomposite dosage, concentration of zinc subgroup ions, solution pH, adsorption temperature and adsorption time. The results revealed that the maximum adsorption capacity onto TLSB was 357.29 mg/g for Zn(II), 458.32 mg/g for Cd(II) and 208.12 mg/g for Hg(II). The adsorption kinetics were explained by the pseudo-second-order model, and the adsorption isotherm conformed to the Langmuir model, implying that the dominant chemical adsorption mechanism on TLSB is monolayer coverage. Thermodynamic studies suggested that the adsorption is spontaneous and endothermic. Desorption and regeneration experiments revealed that TLSB could be desorbed with HCl to recover Zn(II) and Cd(II) and with HNO3 to recover Hg(II) after several consecutive adsorption/desorption cycles. The adsorption mechanism was investigated through FTIR, EDX and SEM, which demonstrated that the introduction of thiol groups improved the adsorption capacity. All of these results suggested that TLSB is an eco-friendly and sustainable adsorbent for the extraction of Zn(II), Cd(II) and Hg(II) ions in aqueous media.
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Nosocomial pneumonia (NP), including ventilator-associated pneumonia (VAP), is increasingly associated with multidrug-resistant Gram-negative pathogens. This study describes the in vitro activity of ceftazidime-avibactam, ceftazidime, and relevant comparator agents against bacterial pathogens isolated from patients with NP, including VAP, enrolled in a ceftazidime-avibactam phase 3 trial. Gram-positive pathogens were included if coisolated with a Gram-negative pathogen. In vitro susceptibility was determined at a central laboratory using Clinical and Laboratory Standards Institute broth microdilution methods. Of 817 randomized patients, 457 (55.9%) had ≥1 Gram-negative bacterial pathogen(s) isolated at baseline, and 149 (18.2%) had ≥1 Gram-positive pathogen(s) coisolated. The most common isolated pathogens were Klebsiella pneumoniae (18.8%), Pseudomonas aeruginosa (15.8%), and Staphylococcus aureus (11.5%). Ceftazidime-avibactam was highly active in vitro against 370 isolates of Enterobacteriaceae, with 98.6% susceptible (MIC90, 0.5 µg/ml) compared with 73.2% susceptible for ceftazidime (MIC90, >64 µg/ml). The percent susceptibility values for ceftazidime-avibactam and ceftazidime against 129 P. aeruginosa isolates were 88.4% and 72.9% (MIC90 values of 16 µg/ml and 64 µg/ml), respectively. Among ceftazidime-nonsusceptible Gram-negative isolates, ceftazidime-avibactam percent susceptibility values were 94.9% for 99 Enterobacteriaceae and 60.0% for 35 P. aeruginosa MIC90 values for linezolid and vancomycin (permitted per protocol for Gram-positive coverage) were within their respective MIC susceptibility breakpoints against the Gram-positive pathogens isolated. This analysis demonstrates that ceftazidime-avibactam was active in vitro against the majority of Enterobacteriaceae and P. aeruginosa isolates from patients with NP, including VAP, in a phase 3 trial. (This study has been registered at ClinicalTrials.gov under identifier NCT01808092.).
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Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Compuestos de Azabiciclo/farmacología , Compuestos de Azabiciclo/uso terapéutico , Ceftazidima/farmacología , Ceftazidima/uso terapéutico , Neumonía Asociada a la Atención Médica/tratamiento farmacológico , Neumonía Asociada a la Atención Médica/microbiología , Neumonía Asociada al Ventilador/tratamiento farmacológico , Neumonía Asociada al Ventilador/microbiología , Inhibidores de beta-Lactamasas/farmacología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Método Doble Ciego , Combinación de Medicamentos , Femenino , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/microbiología , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Adulto JovenRESUMEN
Wood is highly regarded as the most sustainable resource that is widely used in structural applications. To extend its practicality in electrically conductive applications, it is necessary to confer electrical conductivity to the insulating wood. The most common strategy is to derive carbonized wood powder via an annealing process. Even though these carbonized wood powders are electrically conductive, they lost the ancestry characteristic of wood, that is, excellent mechanical properties. As such, it is of great importance to realize the concept of conductive wood while at the same time maintaining or even enhancing its mechanical properties further. By leveraging on the naturally formed transportation channels found in trees, conductive particles can be aligned along these ordered channels. To substitute active transport in living plants, a vacuum pressure impregnation process was used to infiltrate these conductive particles into the transportation channels. As a result, Cu/wood composite, denoted as Cu-SW, exhibited a minimum volume resistivity of 1.366 × 103 Ω cm, which was lower than those of conventional semiconductors. High Cu loading of â¼43.1 volume % of the final product, Cu-SW, was achieved with such technique, which clearly indicates the ability to achieve deep penetration of Cu nanoparticles into the bulk wood. Furthermore, an encouraging mechanical properties improvement of â¼50% was recorded for Cu-SW as compared to the wood matrix. With the enhancement in both conductivity and mechanical properties, Cu-SW could be used in load-bearing application that requires electrical conduction.
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A lignocellulose@ activated clay (Ln@AC) nanocomposite with a hierarchical nanostructure was successfully synthesized by the chemical intercalation reaction and applied in the removal of Zn(II) from an aqueous solution. Ln@AC was characterized by N2 adsorption/desorption isotherms and X-Ray Diffraction (XRD), scanning Electron Microscope (SEM), transmission Electron Microscopy (TEM) and Fourier Transform Infrared Spectroscopy (FTIR) analysis, and the results indicate that an intercalated-exfoliated hierarchical nanostructure was formed. The effects of different adsorption parameters on the Zn(II) removal rate (weight ratio of Ln to AC, Ln@AC dosage, initial Zn(II) concentration, pH value, adsorption temperature, and time) were investigated in detail. The equilibrium adsorption capacity reached 315.9 mg/g under optimal conditions (i.e., the weight ratio of Ln to AC of 3:1, Ln@AC dosage of 1 g/L, initial Zn(II) concentration of 600 mg/L, pH value of 6.8, adsorption temperature of 65 °C, and adsorption time of 50 min). The adsorption process was described by the pseudo-second-order kinetic model, Langmuir isotherm model, and the Elovich model. Moreover, Zn(II) could be easily eluted by HCl, and the effects of HCl concentration, desorption temperature, and ultrasonic desorption time on desorbed amount were tested. Desorption studies revealed that with an HCl concentration of 0.25 mol/L, desorption temperature of 70 °C, and ultrasonic desorption time of 20 min, the maximum desorption capacity and efficiency were achieved at 202.5 mg/g and 64.10%, respectively. Regeneration experimental results indicated that the Ln@AC exhibited a certain recyclable regeneration performance. Due to such outstanding features, the novel Ln@AC nanocomposite proved to have great adsorption potential for Zn(II) removal from wastewater, and exhibited an extremely significant amount of adsorbed Zn(II) when compared to conventional adsorbents.
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Methyl bromide (MB) fumigation is required for U.S. Quercus log exports due to concern over unintentional spread of Bretziella fagacearum. MB alternatives are needed due to the chemical's ability to damage the earth's ozone layer. Vacuum steam (VS) is an environmentally friendly method that was evaluated for its ability to eradicate B. fagacearum in logs (24 to 61 cm diameter; 1.7 to 1.9 m long) obtained from Q. rubra that had wilted following natural infection (NI) or artificial inoculation (AI). Five replicate loads of two NI and one AI logs were VS-treated at 56°C for 30 min and 60°C for 60 min (at 5.0 cm sapwood depth). Mean frequencies of pretreatment fungus colonization ranged from 12.5 to 24.4% in NI and 29.4 to 45.6% in AI logs based on isolation from wood chips of inner and outer sapwood, respectively, of two disks per log. Frequencies of pathogen DNA detection were similar to those for isolation. No viable pathogen or its DNA were detected in posttreatment logs. Treatment times ranged from 5 to 9 h for the 56°C/30 min schedule and from 8 to 10 h for the 60°C/60 min schedule. Based on these results, VS is worthy of further development as a MB alternative.
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Ascomicetos , Desinfección , Quercus , Vapor , Vacio , Madera , Ascomicetos/fisiología , Desinfección/métodos , Quercus/microbiología , Madera/microbiologíaRESUMEN
The bamboo longhorned beetle, Chlorophorus annularis (Fabricius), distributed widely in Asian countries attacking live or postharvest bamboo, is a concern to the international trade of bamboo materials. With the phase out of methyl bromide for quarantine and preshipment use, a reliable, safe, and environmentally friendly phytosanitary treatment is needed as an alternative. In this study, the thermotolerance of C. annularis larvae at atmospheric pressure was examined. The results showed that the thermotolerance increased with instar. The fifth instar was the most thermotolerant stage at 48 and 50°C. A series of vapor heat treatment tests were conducted for bamboo poles infested with C. annularis at the vacuum levels of 15, 30, 50, 70, 90, and 100 kPa at the temperatures of 40, 44, 48, 52, and 56°C with a holding duration of 15 min. The lower pressure or higher temperature increased the mortality of C. annularis. In total 473 larvae were treated at 48°C and 50 kPa for 15 min. Only one larva was found alive, resulting in a mortality rate of 99.7886%. In total 418 larvae were treated at 52°C and 100 kPa for 15 min resulting in 100% mortality. Based on these two results, a heat treatment of 52°C for 15 min at 50 kPa can be used as a low pressure vapor heat treatment for bamboo articles infested with C. annularis. The vapor heat treatment combined with low pressure is an effective alternative phytosanitary measure for bamboo articles.
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Escarabajos , Control de Insectos/métodos , Poaceae , Animales , Calor , LarvaRESUMEN
This research focused on the cell wall structure and its mechanical properties of down-regulated Coumaroyl shikimate 3-hydroxylase (C3H) transgenic poplar and down-regulated hydroxycinnamoyl CoA: shikimate hydroxycinnamoyl transferase (HCT) transgenic poplar (Populus alba × P. glandulosa cv '84 k'). The wood samples with respect to microstructure, the longitudinal elastic modulus (MOE) and hardness of wood fiber secondary cell wall were investigated. The results show that the lignin contents in the two transgenic poplar woods were lower than non-modified wood. The C3H transgenic poplar and HCT transgenic poplar have more than 18.5% and 16.1% cellulose crystalline regions than non-modified poplar respectively. The diameter of the fiber cell and the vessel element of transgenic poplars are smaller. Double radial vessel cell wall thicknesses of both transgenic poplars were smaller than non-modified poplar. Cell wall ratios for the transgenic poplar were higher than non-modified poplar and cell wall density was significantly lower in both C3H and HCT transgenic poplar. The cell wall MOEs of C3H and HCT transgenic poplar was 5.8% and 7.0% higher than non-modified poplar. HCT can be more effective than C3H to modify the trees by considerably increasing mechanical properties of the cell wall.