A nonfused ring electron acceptor(NFREA),designated as TT-Ph-C6,has been synthesized with the aim of enhancing the power conversion efficiency(PCE)of organic solar cells(OSCs).By integrating asymmetric phenylalkylamin...A nonfused ring electron acceptor(NFREA),designated as TT-Ph-C6,has been synthesized with the aim of enhancing the power conversion efficiency(PCE)of organic solar cells(OSCs).By integrating asymmetric phenylalkylamino side groups,TT-Ph-C6 demonstrates excellent solubility and its crystal structure exhibits compact packing structures with a three-dimensional molecular stacking network.These structural attributes markedly promote exciton diffusion and charge carrier mobility,particularly advantageous for the fabrication of thick-film devices.TT-Ph-C6-based devices have attained a PCE of 18.01%at a film thickness of 100 nm,and even at a film thickness of 300 nm,the PCE remains at 14.64%,surpassing that of devices based on 2BTh-2F.These remarkable properties position TT-Ph-C6 as a highly promising NFREA material for boosting the efficiency of OSCs.展开更多
BACKGROUND： Inevitable warm ischemia time before organ procurement aggravates posttransplantation ischemia- reperfusion injury. Endoplasmic reticulum （ER） stress is involved in ischemia-reperfusion injury, but its ...BACKGROUND： Inevitable warm ischemia time before organ procurement aggravates posttransplantation ischemia- reperfusion injury. Endoplasmic reticulum （ER） stress is involved in ischemia-reperfusion injury, but its role in donation after cardiac death （DCD） liver transplantation is not clear and the effect of ER stress inhibitors, tauroursodeoxycholic acid （TUDCA） and 4-phenyl butyric acid （PBA）, on the prognosis of recipient of DCD liver transplantation remains unclear. METHODS： Male Sprague-Dawley rats （8-10 weeks） were randomly divided into control group： liver grafts without warm ischemia were implanted; DCD group： warm ischemia time of the liver grafts was 60 minutes; TUDCA and PBA groups： based on the DCD group, donors were intraperitoneally injected with TUDCA or PBA 30 minutes before the organ procurements. Serum aminotransferase levels, oxidative stress activation and expression of ER stress signal molecules were evaluated. Pathological examinations were performed. The survivals of the recipients in each group were compared for 14 days.RESULTS： Compared with the control group, DCD rats had significantly higher levels of serum aminotransferase at 6 hours, 1 day and 3 days after operation （P〈0.01, 0.01 and 0.05, respectively） and oxidative indices （P〈0.01 for both malondialdehyde and 8-hydroxy deoxyguanosine）, more severe liver damage （P〈0.01） and up-regulated ER stress signal expressions （P〈0.01 for GRP78, phos-eIF2al, CHOP, ATF-4, ATF-6, PERK, XBP-1 and pro-caspase-12）. All recipients died within 3 days after liver transplantation. Administration of TUDCA or PBA significantly decreased aminotransferase levels （P〈0.05）, increased superoxide dismutase activities （P〈0.01）, alleviated liver damage （P〈0.01）, down-regulated ER stress signal expressions （P〈0.01） and improved postoperative survivals （P〈0.01）. CONCLUSIONS： ER stress was involved with DCD liver trans- plantation in rats. Preoperative intraperitoneally injection of TUDCA or PBA protected ER stress and improved prognosis.展开更多
As the scale of residual oil treatment increases and cleaner production improves in China,slurry bubble column reactors face many challenges and opportunities for residual oil hydrogenation technology.The internals de...As the scale of residual oil treatment increases and cleaner production improves in China,slurry bubble column reactors face many challenges and opportunities for residual oil hydrogenation technology.The internals development is critical to adapt the long-term stable operation.In this paper,the volumetric mass transfer coefficient,gas holdup and bubble size in a gas-liquid up-flow column are studied with two kinds of internals.The gas holdup and volumetric mass transfer coefficient increase by 120% and 42% when the fractal dimension of bubbles increases from 0.56 to 2.56,respectively.The enhanced mass transfer processing may improve the coke suppression ability in the slurry reactor for residual oil treatment.The results can be useful for the exploration of reacting conditions,scale-up strategies,and oil adaptability.This work is valuable for the design of reactor systems and technological processes.展开更多
The 2219 aluminum alloy under refilling friction stir welding （RF-FSW） was investi- gated. The micrographs showed that the bead could be divided into six zones, and the grain size and shape were greatly different in...The 2219 aluminum alloy under refilling friction stir welding （RF-FSW） was investi- gated. The micrographs showed that the bead could be divided into six zones, and the grain size and shape were greatly different in these zones. According to the mi- crostructure analysis, the weld nugget zone and the shoulder stirring zone consisted of equiaxed grains, while the grains in the heat affected zone were seriously coars- ened. It was obvious that bending deformation occurred in the thermo-mechanically affected zone. According to the microhardness analysis, the lowest hardness of the weld was at the thermo-mechanically affected zone, and the microhardness increased with the retraction of the stir-pin. The tensile strength and elongation of the bead were 70% and 80% of the base metal, respectively. The tensile strength was slightly different for the stable stage and the retraction stage, while the elongation decreased in the retraction stage. The mechanical different retraction speed were analyzed, with increasing retraction speed. properties and microstrueture responded to and it showed that the elongation decreased展开更多
An increasing number of palaeo-climatic records have been reported to identify the Holocene climate history in the arid Xinjiang region of northwest China. However, few studies have fully considered the internal linka...An increasing number of palaeo-climatic records have been reported to identify the Holocene climate history in the arid Xinjiang region of northwest China. However, few studies have fully considered the internal linkages within the regional climate system, which may limit our understanding of the forcing mechanisms of Holocene climate change in this region. Here, we systematically consider three major issues of the moisture/precipitation, temperature and near-surface wind relevant to the Holocene climate history of Xinjiang. First, despite there still has debated for the Holocene moisture evolution in this region, more climatic reconstructions from lake sediments, loess, sand-dunes and peats support a long-term regional wetting trend. Second, temperature records from ice cores, peats and stalagmites demonstrate a long-term winter warming trend during the Holocene in middle-to high-latitudes of Asia. Third, recent studies of aeolian sedimentary sequences reveal that the near-surface winds in winter gradually weakened during the Holocene, whereas the winter mid-latitude Westerlies strengthened in the Tienshan Mountains. Based on this evidence, in the arid Xinjiang region we propose an early to middle Holocene relatively cold and dry interval, with strong near-surface winds;and a warmer, wetter interval with weaker near-surface winds in the middle to late Holocene during winter. Additionally,we develop a conceptual model to explain the pattern of Holocene climate changes in this region.From the early to the late Holocene, the increasing atmospheric COcontent and winter insolation,and the shrinking of high-latitude continental ice-sheets, resulted in increasing winter temperatures in middle to high latitudes in the Northern Hemisphere. Subsequently, the increased winter temperature strengthened the winter mid-latitude Westerlies and weakened the Siberian high-pressure system,which caused an increase in winter precipitation and a decrease in near-surface wind strength. This scenario is strongly supported by evidence from geological records, climate simulation results, and modern reanalysis data. Our hypothesis highlights the important contribution of winter temperature in driving the Holocene climatic evolution of the arid Xinjiang region, and it implies that the socio-economic development and water resources security of this region will face serious challenges presented by the increasing winter temperature in the future.展开更多
Photothermal material applied in environmental governance has attracted growing attention.By combining the Stober method and dopamine-triggered coating strategy,Co-Mn precursor was in situ incorporated into the poly d...Photothermal material applied in environmental governance has attracted growing attention.By combining the Stober method and dopamine-triggered coating strategy,Co-Mn precursor was in situ incorporated into the poly dopamine(PDA)layer over the surface of silica cores.Afterwards,a unique photothermal nanosphere with SiO_(2)core and thin carbon layer and dual Co-Mn oxides shell was allowed to form by sequential heat treatment in the inert atmosphere(SiO_(2)@CoMn/C).The bimetallic fraction of Co/Mn in the carbon layer and post-treatment calcination temperature was comprehensively tuned to optimize the peroxymonosulfate(PMS)activation performance of the catalyst.The state of bimetallic species was studied including their physical distribution,chemical valence,and interplay by various characterizations.Impressively,Co oxides appear as dominant monodispersed nanoparticles(~10 nm),while Mn with cluster-like morphology is observed to uniformly distribute over thin-layer carbon and adhered to the surface of SiO_(2)nanospheres(~250 nm).The calcined temperature could tune the oxidized state of Co species,leading to the optimization of the catalytic performance of introduced dual metal species.As a result,this obtained optimal catalyst integrated the advantages of exposed bimetallic CoMn species and N-doped thin carbon to deliver excellent catalytic PMS activation performance and photothermal synergetic catalytic mineralization ability for diversiform pollutants.Further reactions condition controls and anion interference studies were conducted to identify the adaptability of the optimal catalyst.Moreover,the application of solar-driven interfacial water evaporation using optimal SiO_(2)@Co_3Mn_1/C-600 catalyst was explored,showing a high water evaporation rate of 1.48 kg·m^(-2)·h^(-1)and an efficiency of 95.2%,further revealing a comprehensive governance functionality of obtained material in the complex pollution condition.展开更多
In this study, surface air temperature from 75 meteorological stations above 3000 m on the Tibetan Plateau are applied for evaluation of the European Centre for Medium-Range Weather Forecasts(ECMWF) third-generation r...In this study, surface air temperature from 75 meteorological stations above 3000 m on the Tibetan Plateau are applied for evaluation of the European Centre for Medium-Range Weather Forecasts(ECMWF) third-generation reanalysis product ERA-Interim in the period of 1979-2010. High correlations ranging from 0.973 to 0.999 indicate that ERA-Interim could capture the annual cycle very well. However, an average root-meansquare error(rmse) of 3.7°C for all stations reveals that ERA-Interim could not be applied directly for the individual sites. The biases can be mainly attributed to the altitude differences between ERA-Interim grid points and stations. An elevation correction method based on monthly lapse rates is limited to reduce the bias for all stations. Generally, ERA-Interim captured the Plateau-Wide annual and seasonal climatologies very well. The spatial variance is highly related to the topographic features of the TP. The temperature increases significantly(10°C- 15°C) from the western to the eastern Tibetan Plateau for all seasons, in particular during winter and summer. A significant warming trend(0.49°C/decade) is found over the entire Tibetan Plateau using station time series from 1979-2010. ERA-Interim captures the annual warming trend with an increase rate of 0.33°C /decade very well. The observation data and ERA-Interim data both showed the largest warming trends in winter with values of 0.67°C/decade and 0.41°C/decade, respectively. We conclude that in general ERA-Interim captures the temperature trends very well and ERA-Interim is reliable for climate change investigation over the Tibetan Plateau under the premise of cautious interpretation.展开更多
Comparative studies on polycyclic aromatic hydrocarbon （PAH） pollution in residential air of Hangzhou （China） and Shizuoka （Japan） were conducted in summer （August,2006） and winter （January,2007）.Total conce...Comparative studies on polycyclic aromatic hydrocarbon （PAH） pollution in residential air of Hangzhou （China） and Shizuoka （Japan） were conducted in summer （August,2006） and winter （January,2007）.Total concentrations of 8 PAHs ranged from 7.1 to 320 ng/m 3 and 0.15 to 35 ng/m 3 in residential air of Hangzhou and Shizuoka,respectively.Air PAH concentrations in smoking houses were higher than that in nonsmoking houses.In nonsmoking houses,mothball emission and cooking practice were the emission sources of 2and 3-ring PAHs in Hangzhou,respectively.The 2and 3-ring PAHs were from use of insect repellent,kerosene heating and outdoor environment in nonsmoking houses in Shizuoka.The 5and 6-ring PAHs in residential air were mainly from outdoor environment in both cities.Toxicity potencies of PAHs in residential air of Hangzhou were much higher than that in Shizuoka.展开更多
Zinc supplementation can help maintain learning and memory function in rodents. In this study, we hypothesized that zinc supplementation could antagonize the neurotoxicity induced by aluminum in rats. Animals were fed...Zinc supplementation can help maintain learning and memory function in rodents. In this study, we hypothesized that zinc supplementation could antagonize the neurotoxicity induced by aluminum in rats. Animals were fed a diet containing different doses of zinc （50, 100, 200 mg/kg） for 9 weeks, and orally administered aluminum chloride （300 mg/kg daily） from the third week for 7 consecutive weeks. Open-field behavioral test results showed that the number of rearings in the group given the 100 mg/kg zinc supplement was significantly increased compared with the group given the 50 mg/kg zinc supplement. Malondialdehyde content in the cerebrum was significantly decreased, while dopamine and 5-hydroxytryptamine levels were increased in the groups given the diet sup- plemented with 100 and 200 mg/kg zinc, compared with the group given the diet supplemented with 50 mg/kg zinc. The acetylcholinesterase activity in the cerebrum was significantly decreased in the group given the 100 mg/kg zinc supplement. Hematoxylin-eosin staining revealed evident patho- logical damage in the hippocampus of rats in the group given the diet supplemented with 50 mg/kg zinc, but the damage was attenuated in the groups given the diet supplemented with 100 and 200 mg/kg zinc. Our findings suggest that zinc is a potential neuroprotective agent against alumi-num-induced neurotoxicity in rats, and the optimal dosages are 100 and 200 mg/kg.展开更多
Silicon monoxide(SiO)has been considered as one of the most promising anode materials for next generation highenergy-density Li-ion batteries(LiBs)thanks to its high theoretical capacity.However,the poor intrinsic ele...Silicon monoxide(SiO)has been considered as one of the most promising anode materials for next generation highenergy-density Li-ion batteries(LiBs)thanks to its high theoretical capacity.However,the poor intrinsic electronic conductivity and large volume change during lithium intercalation/de-intercalation restrict its practical applications.Fabrication of SiO/C composites is an effective way to overcome these problems.Herein,a series of micro-sized SiO@C/graphite(Si0@C/G)composite anode materials,with designed capacity of 600 mAh·g-1,are successfully prepared through a pitch pyrolysis reaction method.The electrochemical performance of SiO@C/G composite anodes with different carbon coating contents of 5 wt%,10 wt%,15 wt%,and 35 wt%is investigated.The results show that the SiO@C/G composite with15-wt%carbon coating content exhibits the best cycle performance,with a high capacity retention of 90.7%at 25℃and90.1%at 450 C after 100 cycles in full cells with LiNi0.5Co0.2Mn0.3O2 as cathodes.The scanning electron microscope(SEM)and electrochemistry impedance spectroscopy(EIS)results suggest that a moderate carbon coating layer can promote the formation of stable SEI film,which is favorable for maintaining good interfacial conductivity and thus enhancing the cycling stability of SiO electrode.展开更多
Glucose fuel cells(GFCs)driven by abiotic catalysts are promising green power sources for portable or wearable devices.In this work,a CoO_(x)incorporated carbon nanofiber(CoO_(x)@CNF)catalyst with mixed valences cobal...Glucose fuel cells(GFCs)driven by abiotic catalysts are promising green power sources for portable or wearable devices.In this work,a CoO_(x)incorporated carbon nanofiber(CoO_(x)@CNF)catalyst with mixed valences cobalt oxides have been developed through partial oxidation of pyrolyzed electrospun Co^(2+)/poly acrylonitrile fibers.The cobalt valence modulating could be achieved via regulating the incorporation ratio of cobalt acetate in precursors or the oxidation temperature of the pyrolyzed fibers.Electrocatalytic analyses show that the presence of CoO in CoO_(x)@CNF will provide more active sites for glucose electrooxidation,and thus enhance the electrocatalytic performance significantly.As a result,the glucose fuel cell built with the CoO.@CNF anode containing both CoO and Co_(3)O_(4)delivered a maximum power density of 270μW cm^(-2),which is higher than that of other reported Co_(3)O_(4)based GFCs.This work provides a simple strategy to develop excellent transition metal catalysts for GFCs to expand their applications in portable and wearable energy devices.展开更多
A model for describing solute segregation at grain boundaries has been developed for substitutional solid solution alloys,which integrates multiple factors from atomic to microstructural scales.A concept of mo-lar Gib...A model for describing solute segregation at grain boundaries has been developed for substitutional solid solution alloys,which integrates multiple factors from atomic to microstructural scales.A concept of mo-lar Gibbs free energy of segregation was introduced to evaluate the segregating capability of the solute elements in a closed system,through which the influences of grain boundary structure,grain size,ma-terial composition,and external conditions were described.Based on the evaluation of various energy forms related to solute segregation and grain growth processes,the nature of the thermal stabilization of nanograin structures by solute segregation was disclosed.A criterion for the destabilization of nanostruc-tures,which is determined by the competition of the change rates between the molar Gibbs free energy of segregation and the total energy of grain boundaries with grain size,has been proposed.This study provided guideline to achieve high-temperature stability of nanograin structures of solid solution alloys even for the weakly segregating nanocrystalline systems.展开更多
Inspired by natural photosynthesis,fabricating high-performance S-scheme heterojunction is regarded as a successful tactic to address energy and environmental issues.Herein,NH_(2)-MIL-125(Ti)/Zn_(0.5)Cd_(0.5)S/NiS(NMT...Inspired by natural photosynthesis,fabricating high-performance S-scheme heterojunction is regarded as a successful tactic to address energy and environmental issues.Herein,NH_(2)-MIL-125(Ti)/Zn_(0.5)Cd_(0.5)S/NiS(NMT/ZCS/NiS)S-scheme heterojunction with interfacial coordination bonds is successfully synthesized through in-situ solvothermal strategy.Notably,the optimal NMT/ZCS/NiS S-scheme heterojunction exhibits comparable photocatalytic H_(2)evolution(PHE)rate of about 14876.7μmol h^(−1)g^(−1)with apparent quantum yield of 24.2%at 420 nm,which is significantly higher than that of recently reported MOFs-based photocatalysts.The interfacial coordination bonds(Zn–N,Cd–N,and Ni–N bonds)accelerate the separation and transfer of photogenerated charges,and the NiS as cocatalyst can provide more catalytically active sites,which synergistically improve the photocatalytic performance.Moreover,theoretical calculation results display that the construction of NMT/ZCS/NiS S-scheme heterojunction also optimize the binding energy of active site-adsorbed hydrogen atoms to enable fast adsorption and desorption.Photoassisted Kelvin probe force microscopy,in-situ irradiation X-ray photoelectron spectroscopy,femtosecond transient absorption spectroscopy,and theoretical calculations provide sufficient evidence of the S-scheme charge migration mechanism.This work offers unique viewpoints for simultaneously accelerating the charge dynamics and optimizing the binding strength between the active sites and hydrogen adsorbates over S-scheme heterojunction.展开更多
Achieving highly-efficient and stable perovskite solar cells(PSCs) with a simplified structure remains challenging, despite the tremendous potential for reducing preparation cost and facile processability by removing ...Achieving highly-efficient and stable perovskite solar cells(PSCs) with a simplified structure remains challenging, despite the tremendous potential for reducing preparation cost and facile processability by removing hole transport layer(HTL). In this work, eco-friendly glucose(Gl) as an interface modifier for HTL-free narrow bandgap tin-lead(Sn-Pb) PSCs is proposed. Gl not only enhances the wettability of the indium tin oxide to promote perovskite heterogeneous nucleation on substrate, but also realizes defect passivation by interacting with uncoordinated Pb^(2+) and Sn^(2+) in perovskite films. As a result, the quality of the perovskite films has been significantly improved, accompanied by reduced defects of bottom interface and optimized energy level structure of device, leading to an efficiency increase and a less nonradiative voltage loss of 0.102 V(for a bandgap of ~1.26 eV). Consequently, the optimized PSC delivers an unprecedented efficiency over 21% with high open-circuit voltage and enhanced stability, outperforming the control device. This work demonstrates a cost-effective approach to develop simplified structure high efficiency HTL-free Sn-Pb PSC.展开更多
目的:探讨动态磁敏感对比增强灌注成像(dynamic susceptibility contrast-perfusion weighted imaging,DSC-PWI)、酰胺质子转移(amide proton transfer,APT)成像在脑胶质瘤分级中的应用价值。方法:回顾性分析2022年1月至2024年9月新疆...目的:探讨动态磁敏感对比增强灌注成像(dynamic susceptibility contrast-perfusion weighted imaging,DSC-PWI)、酰胺质子转移(amide proton transfer,APT)成像在脑胶质瘤分级中的应用价值。方法:回顾性分析2022年1月至2024年9月新疆医科大学第二附属医院收治的100例脑胶质瘤患者的临床资料。根据世界卫生组织(world health organization,WHO)肿瘤分级标准分为低级别组(WHOⅠ~Ⅱ级,n=62)和高级别组(WHOⅢ~Ⅳ级,n=38)。所有患者均于术前接受DSC-PWI、APT成像检查,记录扩散系数(apparent diffusion coefficient,ADC)、脑血容量(cerebral blood volume,CBV)、脑血流量(cerebral blood flow,CBF)、平均通过时间(mean transit time,MTT)、达峰时间(time to peak,TTP)、APT最大值(APT maximum,APTmax)、APT最小值(APT minimum,APTmin)和整个病灶APT平均值(the average APT value of the whole lesion,APTwhole)。比较两组一般资料和ADC、CBV、CBF、MTT、TTP、APTmax、APTmin、APTwhole。多因素Logistic回归分析高级别脑胶质瘤的影响因素。受试者工作特征(Receiver operating characteristic,ROC)曲线分析DSC-PWI联合APT成像对高级别脑胶质瘤的诊断价值。结果:两组在年龄、性别、病灶位置、基底动脉包绕、坏死、生长方式比较,差异无统计学意义(P>0.05),在病灶最大直径≥2 cm、囊性病变比较,差异有统计学意义(P<0.05)。高级别组ADC低于低级别组,APTmax、APTmin、APTwhole、CBF、CBV、MTT和TTP均高于低级别组(P<0.05)。APTmax、APTmin、CBV、MTT和TTP升高是高级别脑胶质瘤的危险因素(P<0.05),ADC升高则是保护因素(P<0.05)。ROC分析结果显示:APTmax、APTmin、ADC、CBV、MTT和TTP诊断高级别脑胶质瘤的曲线下面积(area under the curve,AUC)为0.830、0.868、0.852、0.843、0.803、0.827(均P<0.05)。ROC分析结果显示,Logistic模型对高级别脑胶质瘤诊断的AUC为0.993。结论:DSC-PWI、APT成像参数单一检测在脑胶质瘤分级中均具有较高的诊断价值,且联合检测APTmax、APTmin、ADC、CBV、MTT和TTP成像参数可进一步提高诊断准确性。展开更多
基金Financial support from the National Natural Science Foundation of China(22375024,21975031,21734009,51933001,22109080,and 52173174)the Natural Science Foundation of Shandong Province(No.ZR2022YQ45)+2 种基金the Taishan Scholars Program(Nos.tstp20221121 and tsqnz20221134)The Beijing Natural Science Foundation(No.2244073)supported by State Key Laboratory of Bio-Fibers and Eco-Textiles(Qingdao University)(RZ2200002821)is acknowledged.
文摘A nonfused ring electron acceptor(NFREA),designated as TT-Ph-C6,has been synthesized with the aim of enhancing the power conversion efficiency(PCE)of organic solar cells(OSCs).By integrating asymmetric phenylalkylamino side groups,TT-Ph-C6 demonstrates excellent solubility and its crystal structure exhibits compact packing structures with a three-dimensional molecular stacking network.These structural attributes markedly promote exciton diffusion and charge carrier mobility,particularly advantageous for the fabrication of thick-film devices.TT-Ph-C6-based devices have attained a PCE of 18.01%at a film thickness of 100 nm,and even at a film thickness of 300 nm,the PCE remains at 14.64%,surpassing that of devices based on 2BTh-2F.These remarkable properties position TT-Ph-C6 as a highly promising NFREA material for boosting the efficiency of OSCs.
基金supported by a grant from the National Natural Science Foundation of China (81273262)
文摘BACKGROUND： Inevitable warm ischemia time before organ procurement aggravates posttransplantation ischemia- reperfusion injury. Endoplasmic reticulum （ER） stress is involved in ischemia-reperfusion injury, but its role in donation after cardiac death （DCD） liver transplantation is not clear and the effect of ER stress inhibitors, tauroursodeoxycholic acid （TUDCA） and 4-phenyl butyric acid （PBA）, on the prognosis of recipient of DCD liver transplantation remains unclear. METHODS： Male Sprague-Dawley rats （8-10 weeks） were randomly divided into control group： liver grafts without warm ischemia were implanted; DCD group： warm ischemia time of the liver grafts was 60 minutes; TUDCA and PBA groups： based on the DCD group, donors were intraperitoneally injected with TUDCA or PBA 30 minutes before the organ procurements. Serum aminotransferase levels, oxidative stress activation and expression of ER stress signal molecules were evaluated. Pathological examinations were performed. The survivals of the recipients in each group were compared for 14 days.RESULTS： Compared with the control group, DCD rats had significantly higher levels of serum aminotransferase at 6 hours, 1 day and 3 days after operation （P〈0.01, 0.01 and 0.05, respectively） and oxidative indices （P〈0.01 for both malondialdehyde and 8-hydroxy deoxyguanosine）, more severe liver damage （P〈0.01） and up-regulated ER stress signal expressions （P〈0.01 for GRP78, phos-eIF2al, CHOP, ATF-4, ATF-6, PERK, XBP-1 and pro-caspase-12）. All recipients died within 3 days after liver transplantation. Administration of TUDCA or PBA significantly decreased aminotransferase levels （P〈0.05）, increased superoxide dismutase activities （P〈0.01）, alleviated liver damage （P〈0.01）, down-regulated ER stress signal expressions （P〈0.01） and improved postoperative survivals （P〈0.01）. CONCLUSIONS： ER stress was involved with DCD liver trans- plantation in rats. Preoperative intraperitoneally injection of TUDCA or PBA protected ER stress and improved prognosis.
基金the National Natural Science Foundation of China(51678238,51722806,51608325,21908057)National Key R&D Program of China(2018YFC1802704,2018YFC1801904)+1 种基金China Postdoctoral Science Foundation funded project(2018M641942)Shanghai Sailing Program(19YF1411800)for financial support.
文摘As the scale of residual oil treatment increases and cleaner production improves in China,slurry bubble column reactors face many challenges and opportunities for residual oil hydrogenation technology.The internals development is critical to adapt the long-term stable operation.In this paper,the volumetric mass transfer coefficient,gas holdup and bubble size in a gas-liquid up-flow column are studied with two kinds of internals.The gas holdup and volumetric mass transfer coefficient increase by 120% and 42% when the fractal dimension of bubbles increases from 0.56 to 2.56,respectively.The enhanced mass transfer processing may improve the coke suppression ability in the slurry reactor for residual oil treatment.The results can be useful for the exploration of reacting conditions,scale-up strategies,and oil adaptability.This work is valuable for the design of reactor systems and technological processes.
基金supported by the National Natural Science Foundation of China(Nos.50975176,51035004and51105251)
文摘The 2219 aluminum alloy under refilling friction stir welding （RF-FSW） was investi- gated. The micrographs showed that the bead could be divided into six zones, and the grain size and shape were greatly different in these zones. According to the mi- crostructure analysis, the weld nugget zone and the shoulder stirring zone consisted of equiaxed grains, while the grains in the heat affected zone were seriously coars- ened. It was obvious that bending deformation occurred in the thermo-mechanically affected zone. According to the microhardness analysis, the lowest hardness of the weld was at the thermo-mechanically affected zone, and the microhardness increased with the retraction of the stir-pin. The tensile strength and elongation of the bead were 70% and 80% of the base metal, respectively. The tensile strength was slightly different for the stable stage and the retraction stage, while the elongation decreased in the retraction stage. The mechanical different retraction speed were analyzed, with increasing retraction speed. properties and microstrueture responded to and it showed that the elongation decreased
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program (STEP) (Grant No. 2019QZKK0602)the National Natural Science Foundation of China (Grant Nos. 41401046, 42067049)+1 种基金the Education Science and technology Innovation project of Gansu Province (2021QB-118)the Jiangxi Provincial Natural Science Foundation (Grant No. 20202BABL213035)。
文摘An increasing number of palaeo-climatic records have been reported to identify the Holocene climate history in the arid Xinjiang region of northwest China. However, few studies have fully considered the internal linkages within the regional climate system, which may limit our understanding of the forcing mechanisms of Holocene climate change in this region. Here, we systematically consider three major issues of the moisture/precipitation, temperature and near-surface wind relevant to the Holocene climate history of Xinjiang. First, despite there still has debated for the Holocene moisture evolution in this region, more climatic reconstructions from lake sediments, loess, sand-dunes and peats support a long-term regional wetting trend. Second, temperature records from ice cores, peats and stalagmites demonstrate a long-term winter warming trend during the Holocene in middle-to high-latitudes of Asia. Third, recent studies of aeolian sedimentary sequences reveal that the near-surface winds in winter gradually weakened during the Holocene, whereas the winter mid-latitude Westerlies strengthened in the Tienshan Mountains. Based on this evidence, in the arid Xinjiang region we propose an early to middle Holocene relatively cold and dry interval, with strong near-surface winds;and a warmer, wetter interval with weaker near-surface winds in the middle to late Holocene during winter. Additionally,we develop a conceptual model to explain the pattern of Holocene climate changes in this region.From the early to the late Holocene, the increasing atmospheric COcontent and winter insolation,and the shrinking of high-latitude continental ice-sheets, resulted in increasing winter temperatures in middle to high latitudes in the Northern Hemisphere. Subsequently, the increased winter temperature strengthened the winter mid-latitude Westerlies and weakened the Siberian high-pressure system,which caused an increase in winter precipitation and a decrease in near-surface wind strength. This scenario is strongly supported by evidence from geological records, climate simulation results, and modern reanalysis data. Our hypothesis highlights the important contribution of winter temperature in driving the Holocene climatic evolution of the arid Xinjiang region, and it implies that the socio-economic development and water resources security of this region will face serious challenges presented by the increasing winter temperature in the future.
基金financially supported by the China National Natural Science Foundation(No.21908085)China Postdoctoral Science Foundation(No.2022M711686)Jiangsu Provincial Founds for the Young Scholars(No.BK20190961)。
文摘Photothermal material applied in environmental governance has attracted growing attention.By combining the Stober method and dopamine-triggered coating strategy,Co-Mn precursor was in situ incorporated into the poly dopamine(PDA)layer over the surface of silica cores.Afterwards,a unique photothermal nanosphere with SiO_(2)core and thin carbon layer and dual Co-Mn oxides shell was allowed to form by sequential heat treatment in the inert atmosphere(SiO_(2)@CoMn/C).The bimetallic fraction of Co/Mn in the carbon layer and post-treatment calcination temperature was comprehensively tuned to optimize the peroxymonosulfate(PMS)activation performance of the catalyst.The state of bimetallic species was studied including their physical distribution,chemical valence,and interplay by various characterizations.Impressively,Co oxides appear as dominant monodispersed nanoparticles(~10 nm),while Mn with cluster-like morphology is observed to uniformly distribute over thin-layer carbon and adhered to the surface of SiO_(2)nanospheres(~250 nm).The calcined temperature could tune the oxidized state of Co species,leading to the optimization of the catalytic performance of introduced dual metal species.As a result,this obtained optimal catalyst integrated the advantages of exposed bimetallic CoMn species and N-doped thin carbon to deliver excellent catalytic PMS activation performance and photothermal synergetic catalytic mineralization ability for diversiform pollutants.Further reactions condition controls and anion interference studies were conducted to identify the adaptability of the optimal catalyst.Moreover,the application of solar-driven interfacial water evaporation using optimal SiO_(2)@Co_3Mn_1/C-600 catalyst was explored,showing a high water evaporation rate of 1.48 kg·m^(-2)·h^(-1)and an efficiency of 95.2%,further revealing a comprehensive governance functionality of obtained material in the complex pollution condition.
基金funded by Fujian Bureau of Surveying,Mapping and Geoinformation(Grant No.2013S17)Natural Science Foundation of China(Grant No.71373130)+2 种基金Non-Profit Research Projects of Fujian Province,China(Grant No2013R04)Key Project of the Department of Science and Technology of Fujian Province,China(Grant No.2012Y4001)supported by the ECMWF’s public web server(http://apps.ecmwf.int/datasets/)
文摘In this study, surface air temperature from 75 meteorological stations above 3000 m on the Tibetan Plateau are applied for evaluation of the European Centre for Medium-Range Weather Forecasts(ECMWF) third-generation reanalysis product ERA-Interim in the period of 1979-2010. High correlations ranging from 0.973 to 0.999 indicate that ERA-Interim could capture the annual cycle very well. However, an average root-meansquare error(rmse) of 3.7°C for all stations reveals that ERA-Interim could not be applied directly for the individual sites. The biases can be mainly attributed to the altitude differences between ERA-Interim grid points and stations. An elevation correction method based on monthly lapse rates is limited to reduce the bias for all stations. Generally, ERA-Interim captured the Plateau-Wide annual and seasonal climatologies very well. The spatial variance is highly related to the topographic features of the TP. The temperature increases significantly(10°C- 15°C) from the western to the eastern Tibetan Plateau for all seasons, in particular during winter and summer. A significant warming trend(0.49°C/decade) is found over the entire Tibetan Plateau using station time series from 1979-2010. ERA-Interim captures the annual warming trend with an increase rate of 0.33°C /decade very well. The observation data and ERA-Interim data both showed the largest warming trends in winter with values of 0.67°C/decade and 0.41°C/decade, respectively. We conclude that in general ERA-Interim captures the temperature trends very well and ERA-Interim is reliable for climate change investigation over the Tibetan Plateau under the premise of cautious interpretation.
基金supported by the Zhejiang Provincial Natural Science Foundation of China (No.Y5100309,Z5100294)the China Postdoctoral Science Foundation (No.20100471698)+1 种基金the S&T Plan Projects of Zhejiang Provincial Education Department (No.Y201017541)the Program of Zhejiang Provincial Science and Technology Department (No.2010C33059)
文摘Comparative studies on polycyclic aromatic hydrocarbon （PAH） pollution in residential air of Hangzhou （China） and Shizuoka （Japan） were conducted in summer （August,2006） and winter （January,2007）.Total concentrations of 8 PAHs ranged from 7.1 to 320 ng/m 3 and 0.15 to 35 ng/m 3 in residential air of Hangzhou and Shizuoka,respectively.Air PAH concentrations in smoking houses were higher than that in nonsmoking houses.In nonsmoking houses,mothball emission and cooking practice were the emission sources of 2and 3-ring PAHs in Hangzhou,respectively.The 2and 3-ring PAHs were from use of insect repellent,kerosene heating and outdoor environment in nonsmoking houses in Shizuoka.The 5and 6-ring PAHs in residential air were mainly from outdoor environment in both cities.Toxicity potencies of PAHs in residential air of Hangzhou were much higher than that in Shizuoka.
基金was funded by the National Nature Science Foundation of China,No.30872098,30901185the National Nature Science Foundation of Tianjin,No.05YFJMJC 05500the Medical Science and Technology Project of Chinese PLA,No.13QNP069.
文摘Zinc supplementation can help maintain learning and memory function in rodents. In this study, we hypothesized that zinc supplementation could antagonize the neurotoxicity induced by aluminum in rats. Animals were fed a diet containing different doses of zinc （50, 100, 200 mg/kg） for 9 weeks, and orally administered aluminum chloride （300 mg/kg daily） from the third week for 7 consecutive weeks. Open-field behavioral test results showed that the number of rearings in the group given the 100 mg/kg zinc supplement was significantly increased compared with the group given the 50 mg/kg zinc supplement. Malondialdehyde content in the cerebrum was significantly decreased, while dopamine and 5-hydroxytryptamine levels were increased in the groups given the diet sup- plemented with 100 and 200 mg/kg zinc, compared with the group given the diet supplemented with 50 mg/kg zinc. The acetylcholinesterase activity in the cerebrum was significantly decreased in the group given the 100 mg/kg zinc supplement. Hematoxylin-eosin staining revealed evident patho- logical damage in the hippocampus of rats in the group given the diet supplemented with 50 mg/kg zinc, but the damage was attenuated in the groups given the diet supplemented with 100 and 200 mg/kg zinc. Our findings suggest that zinc is a potential neuroprotective agent against alumi-num-induced neurotoxicity in rats, and the optimal dosages are 100 and 200 mg/kg.
基金Project supported by the State Grid Technology Project,China(study on the mechanism and characterization of lithium dendrite growth in lithium ion batteries,Project No.DG71-17-010)the National Key Research and Development Program of China(Grant No.2017YFB0102004)the National Natural Science Foundation of China(Grant No.51822211)
文摘Silicon monoxide(SiO)has been considered as one of the most promising anode materials for next generation highenergy-density Li-ion batteries(LiBs)thanks to its high theoretical capacity.However,the poor intrinsic electronic conductivity and large volume change during lithium intercalation/de-intercalation restrict its practical applications.Fabrication of SiO/C composites is an effective way to overcome these problems.Herein,a series of micro-sized SiO@C/graphite(Si0@C/G)composite anode materials,with designed capacity of 600 mAh·g-1,are successfully prepared through a pitch pyrolysis reaction method.The electrochemical performance of SiO@C/G composite anodes with different carbon coating contents of 5 wt%,10 wt%,15 wt%,and 35 wt%is investigated.The results show that the SiO@C/G composite with15-wt%carbon coating content exhibits the best cycle performance,with a high capacity retention of 90.7%at 25℃and90.1%at 450 C after 100 cycles in full cells with LiNi0.5Co0.2Mn0.3O2 as cathodes.The scanning electron microscope(SEM)and electrochemistry impedance spectroscopy(EIS)results suggest that a moderate carbon coating layer can promote the formation of stable SEI film,which is favorable for maintaining good interfacial conductivity and thus enhancing the cycling stability of SiO electrode.
基金We gratefully acknowledge to the financial support from the Chongqing Key Laboratory for Advanced MaterialsTechnologies of Clean Energies and Academician Station of Hainan Province(SQ2021PTZ0024).
文摘Glucose fuel cells(GFCs)driven by abiotic catalysts are promising green power sources for portable or wearable devices.In this work,a CoO_(x)incorporated carbon nanofiber(CoO_(x)@CNF)catalyst with mixed valences cobalt oxides have been developed through partial oxidation of pyrolyzed electrospun Co^(2+)/poly acrylonitrile fibers.The cobalt valence modulating could be achieved via regulating the incorporation ratio of cobalt acetate in precursors or the oxidation temperature of the pyrolyzed fibers.Electrocatalytic analyses show that the presence of CoO in CoO_(x)@CNF will provide more active sites for glucose electrooxidation,and thus enhance the electrocatalytic performance significantly.As a result,the glucose fuel cell built with the CoO.@CNF anode containing both CoO and Co_(3)O_(4)delivered a maximum power density of 270μW cm^(-2),which is higher than that of other reported Co_(3)O_(4)based GFCs.This work provides a simple strategy to develop excellent transition metal catalysts for GFCs to expand their applications in portable and wearable energy devices.
基金supported by the Beijing Natural Science Foun-dation(No.2214067)the National Key R&D Program of China(Nos.2021YFB3501502 and 2021YFB3501504)the National Natural Science Foundation of China(No.92163107).
文摘A model for describing solute segregation at grain boundaries has been developed for substitutional solid solution alloys,which integrates multiple factors from atomic to microstructural scales.A concept of mo-lar Gibbs free energy of segregation was introduced to evaluate the segregating capability of the solute elements in a closed system,through which the influences of grain boundary structure,grain size,ma-terial composition,and external conditions were described.Based on the evaluation of various energy forms related to solute segregation and grain growth processes,the nature of the thermal stabilization of nanograin structures by solute segregation was disclosed.A criterion for the destabilization of nanostruc-tures,which is determined by the competition of the change rates between the molar Gibbs free energy of segregation and the total energy of grain boundaries with grain size,has been proposed.This study provided guideline to achieve high-temperature stability of nanograin structures of solid solution alloys even for the weakly segregating nanocrystalline systems.
文摘Inspired by natural photosynthesis,fabricating high-performance S-scheme heterojunction is regarded as a successful tactic to address energy and environmental issues.Herein,NH_(2)-MIL-125(Ti)/Zn_(0.5)Cd_(0.5)S/NiS(NMT/ZCS/NiS)S-scheme heterojunction with interfacial coordination bonds is successfully synthesized through in-situ solvothermal strategy.Notably,the optimal NMT/ZCS/NiS S-scheme heterojunction exhibits comparable photocatalytic H_(2)evolution(PHE)rate of about 14876.7μmol h^(−1)g^(−1)with apparent quantum yield of 24.2%at 420 nm,which is significantly higher than that of recently reported MOFs-based photocatalysts.The interfacial coordination bonds(Zn–N,Cd–N,and Ni–N bonds)accelerate the separation and transfer of photogenerated charges,and the NiS as cocatalyst can provide more catalytically active sites,which synergistically improve the photocatalytic performance.Moreover,theoretical calculation results display that the construction of NMT/ZCS/NiS S-scheme heterojunction also optimize the binding energy of active site-adsorbed hydrogen atoms to enable fast adsorption and desorption.Photoassisted Kelvin probe force microscopy,in-situ irradiation X-ray photoelectron spectroscopy,femtosecond transient absorption spectroscopy,and theoretical calculations provide sufficient evidence of the S-scheme charge migration mechanism.This work offers unique viewpoints for simultaneously accelerating the charge dynamics and optimizing the binding strength between the active sites and hydrogen adsorbates over S-scheme heterojunction.
基金supported by the National Natural Science Foundation of China (Grant No. 12074321)the Young Science and Technology Talents Development Project of Guizhou Provincial Education Department (Grant No. QJH-KY [2022]012)+2 种基金the Fundamental Research Funds for the Central Universities (Grant No. SWU020019)the Natural Science Foundation of Chongqing (Grant No. cstc2020jcyjmsxmx0648)the Chongqing Graduate Student Research Innovation Project (Grant No. CYB22119)。
文摘Achieving highly-efficient and stable perovskite solar cells(PSCs) with a simplified structure remains challenging, despite the tremendous potential for reducing preparation cost and facile processability by removing hole transport layer(HTL). In this work, eco-friendly glucose(Gl) as an interface modifier for HTL-free narrow bandgap tin-lead(Sn-Pb) PSCs is proposed. Gl not only enhances the wettability of the indium tin oxide to promote perovskite heterogeneous nucleation on substrate, but also realizes defect passivation by interacting with uncoordinated Pb^(2+) and Sn^(2+) in perovskite films. As a result, the quality of the perovskite films has been significantly improved, accompanied by reduced defects of bottom interface and optimized energy level structure of device, leading to an efficiency increase and a less nonradiative voltage loss of 0.102 V(for a bandgap of ~1.26 eV). Consequently, the optimized PSC delivers an unprecedented efficiency over 21% with high open-circuit voltage and enhanced stability, outperforming the control device. This work demonstrates a cost-effective approach to develop simplified structure high efficiency HTL-free Sn-Pb PSC.
文摘目的:探讨动态磁敏感对比增强灌注成像(dynamic susceptibility contrast-perfusion weighted imaging,DSC-PWI)、酰胺质子转移(amide proton transfer,APT)成像在脑胶质瘤分级中的应用价值。方法:回顾性分析2022年1月至2024年9月新疆医科大学第二附属医院收治的100例脑胶质瘤患者的临床资料。根据世界卫生组织(world health organization,WHO)肿瘤分级标准分为低级别组(WHOⅠ~Ⅱ级,n=62)和高级别组(WHOⅢ~Ⅳ级,n=38)。所有患者均于术前接受DSC-PWI、APT成像检查,记录扩散系数(apparent diffusion coefficient,ADC)、脑血容量(cerebral blood volume,CBV)、脑血流量(cerebral blood flow,CBF)、平均通过时间(mean transit time,MTT)、达峰时间(time to peak,TTP)、APT最大值(APT maximum,APTmax)、APT最小值(APT minimum,APTmin)和整个病灶APT平均值(the average APT value of the whole lesion,APTwhole)。比较两组一般资料和ADC、CBV、CBF、MTT、TTP、APTmax、APTmin、APTwhole。多因素Logistic回归分析高级别脑胶质瘤的影响因素。受试者工作特征(Receiver operating characteristic,ROC)曲线分析DSC-PWI联合APT成像对高级别脑胶质瘤的诊断价值。结果:两组在年龄、性别、病灶位置、基底动脉包绕、坏死、生长方式比较,差异无统计学意义(P>0.05),在病灶最大直径≥2 cm、囊性病变比较,差异有统计学意义(P<0.05)。高级别组ADC低于低级别组,APTmax、APTmin、APTwhole、CBF、CBV、MTT和TTP均高于低级别组(P<0.05)。APTmax、APTmin、CBV、MTT和TTP升高是高级别脑胶质瘤的危险因素(P<0.05),ADC升高则是保护因素(P<0.05)。ROC分析结果显示:APTmax、APTmin、ADC、CBV、MTT和TTP诊断高级别脑胶质瘤的曲线下面积(area under the curve,AUC)为0.830、0.868、0.852、0.843、0.803、0.827(均P<0.05)。ROC分析结果显示,Logistic模型对高级别脑胶质瘤诊断的AUC为0.993。结论:DSC-PWI、APT成像参数单一检测在脑胶质瘤分级中均具有较高的诊断价值,且联合检测APTmax、APTmin、ADC、CBV、MTT和TTP成像参数可进一步提高诊断准确性。
