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Enhancing lead-free photovoltaic performance:Minimizing buried surface voids in tin perovskite films through weakly polar solvent pre-treatment strategy
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作者 Dongdong Yan Han Zhang +7 位作者 Chensi Gong Hailong Wang Qing Lu Jun Liu Wenzhen Lv Mingguang Li Runfeng Chen Ligang Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期556-561,共6页
Buried interfacial voids have always been a notorious phenomenon observed in the fabrication of lead perovskite films. The existence of interfacial voids at the buried interface will capture the carrier, suppress carr... Buried interfacial voids have always been a notorious phenomenon observed in the fabrication of lead perovskite films. The existence of interfacial voids at the buried interface will capture the carrier, suppress carrier transport efficiencies, and affect the stability of photovoltaic devices. However, the impact of these buried interfacial voids on tin perovskites, a promising avenue for advancing lead-free photovoltaics, has been largely overlooked. Here, we utilize an innovative weakly polar solvent pretreatment strategy(WPSPS) to mitigate buried interfacial voids of tin perovskites. Our investigation reveals the presence of numerous voids in tin perovskites during annealing, attributed to trapped dimethyl sulfoxide(DMSO) used in film formation. The WPSPS method facilitates accelerated DMSO evaporation, effectively reducing residual DMSO. Interestingly, the WPSPS shifts the energy level of PEDOT:PSS downward, making it more aligned with the perovskite. This alignment enhances the efficiency of charge carrier transport. As the result, tin perovskite film quality is significantly improved,achieving a maximum power conversion efficiency approaching 12% with only an 8.3% efficiency loss after 1700 h of stability tests, which compares well with the state-of-the-art stability of tin-based perovskite solar cells. 展开更多
关键词 Tin perovskite Buried interfacial Weakly polar solvent pre-treatment strategy
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Influence of low-vacuum helium cold plasma pre-treatment on the rooting and root growth of zoysiagrass(Zoysia Willd.) stolon cuttings 被引量:1
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作者 Ling LI Hailin GUO +6 位作者 Junqin ZONG Jingbo CHEN Yi WANG Jianjian LI Dandan LI Hanliang SHAO Jianxiu LIU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第5期162-167,共6页
The influence of low-vacuum helium cold plasma treatment on the rooting percentage,root growth and physiochemical properties of zoysiagrass stolon cuttings was studied.Zoysiagrass stolon cuttings were pre-treated with... The influence of low-vacuum helium cold plasma treatment on the rooting percentage,root growth and physiochemical properties of zoysiagrass stolon cuttings was studied.Zoysiagrass stolon cuttings were pre-treated with 0,100,200,300 and 400 W of cold plasma for 15 s.The cold plasma positively stimulated rooting and improved the root growth of the zoysiagrass stolon cuttings,and the 300 W treatment produced the best effect.The rooting percentage and root growth parameters,including the root length,total root surface area,total root volume,average root diameter,and root dry weight,significantly improved in response to the cold plasma treatment.In addition,the water uptake and relative conductivity of the stolon cuttings increased significantly in response to the cold plasma treatment.The results revealed that cold plasma-stimulated rooting and root growth appear to be a consequence of the improvement in permeability and water absorbing capacity of zoysiagrass stolon cuttings.The results of the present study will provide inspiration and support for the application of cold plasma in the vegetative propagation of plants. 展开更多
关键词 cold plasma zoysiagrass STOLON CUTTING ROOTING ROOT growth
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High corrosion resistance of electroless Ni-P with chromium-free conversion pre-treatments on AZ91D magnesium alloy 被引量:5
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作者 J.SUDAGAR 连建设 +2 位作者 陈晓明 朗鹏 梁亚琴 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第4期921-928,共8页
Phosphate-manganese, tannic acid and vanadium conversion coatings were proposed as an effective pre-treatment layer between electroless Ni-P coating and AZ91D magnesium alloy substrate to replace the traditional chrom... Phosphate-manganese, tannic acid and vanadium conversion coatings were proposed as an effective pre-treatment layer between electroless Ni-P coating and AZ91D magnesium alloy substrate to replace the traditional chromate plus HF pre-treatment. The electrochemical results show that the chrome-free coatings plus electroless Ni-P coating on the magnesium alloy has the lowest corrosion current density and most positive corrosion potential compared with chromate plus electroless Ni-P coating on the magnesium alloy. These proposed pre-treatment layers on the substrate reduce the corrosion of magnesium during plating process, and reduce the potential difference between the matrix and the second phase. Thus, an electroless Ni-P coating with fine crystalline and dense structure was obtained, with preferential phosphorus content, low porosity, good corrosion-resistance and strengthened adhesion than the chromate plus electroless Ni-P. 展开更多
关键词 magnesium alloy corrosion resistance ELECTROLESS chromium-free pre-treatment
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汉英温觉词“冷/cold”的隐喻对比研究
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作者 吕兆格 唐远远 《开封文化艺术职业学院学报》 2024年第5期62-66,共5页
温度是人类最早的认知领域之一。汉语和英语中存在大量描述温度感觉的词语,它们既指身体感知到的温度概念,又能映射到人类的心理态度等范畴,表达由温度义引申出的其他概念。文章从认知语言学的视角出发,借助隐喻理论,系统梳理汉英温觉... 温度是人类最早的认知领域之一。汉语和英语中存在大量描述温度感觉的词语,它们既指身体感知到的温度概念,又能映射到人类的心理态度等范畴,表达由温度义引申出的其他概念。文章从认知语言学的视角出发,借助隐喻理论,系统梳理汉英温觉词“冷/cold”基于身体认知的隐喻映射,得出语域映射的基本模式和结论。此外,受语言文化等因素的影响,“冷/cold”的隐喻映射也呈现出一种同异并存的现象。 展开更多
关键词 cold 温觉词 隐喻 汉英对比
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Comparison of pre-treatment and post-treatment use of selenium in retinal ischemia reperfusion injury 被引量:3
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作者 Alper Yazici Hasan Aksit +6 位作者 Esin Sogutlu Sari Arzu Yay Haydar Ali Erken Dilek Aksit Harun Cakmak Kamil Seyrek Sitki Samet Ermis 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第2期263-268,共6页
AIM: To investigate the effects of selenium in rat retinal ischemia reperfusion(IR) model and compare pretreatment and post-treatment use.METHODS: Selenium pre-treatment group(n =8) was treated with intraperitoneal(i.... AIM: To investigate the effects of selenium in rat retinal ischemia reperfusion(IR) model and compare pretreatment and post-treatment use.METHODS: Selenium pre-treatment group(n =8) was treated with intraperitoneal(i.p.) selenium 0.5 mg/kg for7 d and terminated 24 h after the IR injury. Selenium posttreatment group( n = 8) was treated with i. p. selenium0.5 mg/kg for 7d after the IR injury with termination at the end of the 7d period. Sham group(n =8) received i.p.saline injections identical to the selenium volume for 7d with termination 24 h after the IR injury. Control group(n =8) received no intervention. Main outcome measures were retina superoxide dismutase(SOD), glutathione(GSH),total antioxidant status(TAS), malondialdehyde(MDA),DNA fragmentation levels, and immunohistological apoptosis evaluation.RESULTS: Compared to the Sham group, selenium pre-treatment had a statistical difference in all parameters except SOD. Post-treatment selenium also resulted in statistical differences in all parameters except the MDA levels. When comparing selenium groups, the pre-treatment selenium group had a statistically higher success in reduction of markers of cell damage such as MDA and DNA fragmentation. In contrast, the post-selenium treatment group had resulted in statisticallyhigher levels of GSH. Histologically both selenium groups succeeded to limit retinal thickening and apoptosis. Pre-treatment use was statistically more successful in decreasing apoptosis in ganglion cell layer compared to post-treatment use.CONCLUSION: Selenium was successful in retinal protection in IR injuries. Pre-treatment efficacy was superior in terms of prevention of tissue damage and apoptosis. 展开更多
关键词 RETINA SELENIUM ISCHEMIA-REPERFUSION APOPTOSIS pre-treatment POST-TREATMENT oxidative stress
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Effect of Cross-flow Velocity on the Critical Flux of Ceramic Membrane Filtration as a Pre-treatment for Seawater Desalination 被引量:3
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作者 崔朝亮 彭文博 +2 位作者 范益群 邢卫红 徐南平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第4期341-347,共7页
Pre-treatment, which supplies a stable, high-quality feed for reverse osmosis (RO) membranes, is a criti- cal step for successful operation in a seawater reverse osmosis plant. In this study, ceramic membrane system... Pre-treatment, which supplies a stable, high-quality feed for reverse osmosis (RO) membranes, is a criti- cal step for successful operation in a seawater reverse osmosis plant. In this study, ceramic membrane systems were employed as pre-treatment for seawater desalination. A laboratory experiment was performed to investigate the effect of the cross-flow velocity on the critical flux and consequently to optimize the permeate flux. Then a pilot test was performed to investigate the long-term performance. The result shows that there is no significant effect of the cross-flow velocity on the critical flux when the cross-flow velocity varies in laminar flow region only or in turbulent flow region only, but the effect is distinct when the cross-flow velocity varies in the transition region. The membrane fouling is slight at the permeate flux of 150 L·m^-2·h^-1 and the system is stable, producing a high-quality feed (the turbidity and silt density index are less than 0.1 NTU and 3.0, respectively) for RO to run for 2922.4 h without chemical cleaning. Thus the ceramic membranes are suitable to filtrate seawater as the pre-treatment for RO. 展开更多
关键词 ceramic membrane seawater desalination pre-treatment critical flux
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Effect of microwave pre-treatment on physical quality,bioactive compounds,safety risk factor,and storage stability of peanut butter 被引量:7
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作者 Jefferson G.Degon Chang Zheng +3 位作者 Abdeen Elkhedir Bo Yang Qi Zhou Wenlin Li 《Oil Crop Science》 CSCD 2021年第3期137-144,共8页
Microwave,as a new heat treatment technology,has the characteristics of uniform and fast heating speed.It is an energy-saving technology known for improving oilseed product quality.Its efficiency mainly depends on the... Microwave,as a new heat treatment technology,has the characteristics of uniform and fast heating speed.It is an energy-saving technology known for improving oilseed product quality.Its efficiency mainly depends on the roasting power and time.However,the production of high-quality peanut butter using short-time roasting con-ditions are limited.Herein,we determined an appropriate microwave roasting power and time for peanuts and evaluated its impacts on the quality of peanut butter.Different roasting powers(400 W,800 W and 1200 W)and times(4,4.5,5,and 5.5 min)were preliminarily tested.Among them,800 W at 5 min was the most suitable.The roasting efficiency was further evaluated using color,sensory,bioactive compounds,storage stability,and safety risk factors of peanut butter produced from four peanut cultivars(Silihong,Baisha-1016,Yuanza-9102,and Yuhua-9414).The pre-treated butter obtained from three cultivars(Silihong,Yuanza-9102,and Yuhua-9414)with moisture content between 5%and 7.2%had a similar sensory score(6-7)as the commercial on a 9-point hedonic scale compare to the other.The color of the pre-treated peanut butter varies statistically with the commercial but remained in the recommended range of Hunter L*values of 51-52,respectively,for high initial moisture peanut cultivars.The total polyphenol(35.20-31.59±0.59μmol GAE/g)and tocopherol(19.05±0.35 mg/100 g)content in the butter obtained from three cultivars(Yuahua-9102,Yuhua,and Baisha-1016)and Silihong respectively,were significantly(P<0.05)higher than those in the commercial butter.The induction times of all pre-treated butter(19.80±0.99-7.84±0.07 h)were significantly(P<0.05)longer during storage at accelerated temperature than commercial samples.In addition,no benzo[a]pyrene was found in the pre-treated samples.Collectively,the microwave pretreated peanut butter was superior to the commercial one.These findings provided data support and a reference basis to promote microwave use for peanut butter production. 展开更多
关键词 Microwave pre-treatment Peanut butter SENSORY Storage stability:bioactive compounds
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Effects of thrombopoietin pre-treatment on peri-liver transplantation thrombocytopenia in a mouse model of cirrhosis with hypersplenism 被引量:2
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作者 Zi-Rong Liu Ya-Min Zhang +1 位作者 Zi-Lin Cui Wen Tong 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第10期2115-2122,共8页
BACKGROUND During cirrhosis,the liver is impaired and unable to synthesize and clear thrombopoietin properly.At the same time,the spleen assumes the function of hemofiltration and storage due to liver dysfunction,resu... BACKGROUND During cirrhosis,the liver is impaired and unable to synthesize and clear thrombopoietin properly.At the same time,the spleen assumes the function of hemofiltration and storage due to liver dysfunction,resulting in hypersplenism and excessive removal of platelets in the spleen,further reducing platelet count.When liver function is decompensated in cirrhotic patients,the decrease of thrombopoietin(TPO)synthesis is the main reason for the decrease of new platelet production.This change of TPO leads to thrombocytopenia and bleeding tendency in cirrhotic patients with hypersplenism.AIM To investigate the clinical efficacy of recombinant human TPO(rhTPO)in the treatment of perioperative thrombocytopenia during liver transplantation in cirrhotic mice with hypersplenism.METHODS C57BL/6J mice and TPO receptor-deficient mice were used to establish models of cirrhosis with hypersplenism.Subsequently,these mice underwent orthotopic liver transplantation(OLT).The mice in the experimental group were given rhTPO treatment for 3 consecutive days before surgery and 5 consecutive days after surgery,while the mice in the control group received the same dose of saline at the same frequency.Differences in liver function and platelet counts were determined between the experimental and control groups.Enzyme-linked immunosorbent assay was used to assess the expression of TPO and TPO receptor(c-Mpl)in the blood.RESULTS Preoperative administration of rhTPO significantly improved peri-OLT thrombocytopenia in mice with cirrhosis and hypersplenism.Blocking the expression of TPO receptors exacerbated peri-OLT thrombocytopenia.The concentration of TPO decreased while the concentration of c-Mpl increased in compensation in the mouse model of cirrhosis with hypersplenism.TPO pre-treatment significantly increased the postoperative TPO concentration in mice,which in turn led to a decrease in the c-Mpl concentration.TPO pre-treatment also significantly enhanced the Janus kinase(Jak)/signal transducers and activators of transcription pathway protein expressions in bone marrow stem cells of the C57BL/6J mice.Moreover,the administration of TPO,both before and after surgery,regulated the levels of biochemical indicators,such as alanine aminotransferase,alkaline phosphatase,and aspartate aminotransferase in the C57BL/6J mice.CONCLUSION Pre-treatment with TPO not only exhibited therapeutic effects on perioperative thrombocytopenia in the mice with cirrhosis and hypersplenism,who underwent liver transplantation but also significantly enhanced the perioperative liver function. 展开更多
关键词 Thrombopoietin pre-treatment CIRRHOSIS Liver transplantation Perioperative period PLATELET
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Artificial neural network approach for rheological characteristics of coal-water slurry using microwave pre-treatment 被引量:3
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作者 B.K.Sahoo S.De B.C.Meikap 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第2期379-386,共8页
Detailed experimental investigations were carried out for microwave pre-treatment of high ash Indian coal at high power level(900 W) in microwave oven. The microwave exposure times were fixed at60 s and 120 s. A rheol... Detailed experimental investigations were carried out for microwave pre-treatment of high ash Indian coal at high power level(900 W) in microwave oven. The microwave exposure times were fixed at60 s and 120 s. A rheology characteristic for microwave pre-treatment of coal-water slurry(CWS) was performed in an online Bohlin viscometer. The non-Newtonian character of the slurry follows the rheological model of Ostwald de Waele. The values of n and k vary from 0.31 to 0.64 and 0.19 to 0.81 Pa·sn,respectively. This paper presents an artificial neural network(ANN) model to predict the effects of operational parameters on apparent viscosity of CWS. A 4-2-1 topology with Levenberg-Marquardt training algorithm(trainlm) was selected as the controlled ANN. Mean squared error(MSE) of 0.002 and coefficient of multiple determinations(R^2) of 0.99 were obtained for the outperforming model. The promising values of correlation coefficient further confirm the robustness and satisfactory performance of the proposed ANN model. 展开更多
关键词 Microwave pre-treatment Coal-water slurry Apparent viscosity Artificial neural network Back propagation algorithm
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Tree-ring δ^(15)N of Qinghai spruce in the central Qilian Mountains of China:Is pre-treatment of wood samples necessary? 被引量:2
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作者 WANG Ziyi LIU Xiaohong +5 位作者 WANG Keyi ZENG Xiaomin ZHANG Yu GE Wensen KANG Huhu LU Qiangqiang 《Journal of Arid Land》 SCIE CSCD 2022年第6期673-690,共18页
A knowledge of the tree-ring stable nitrogen isotope ratio(δ^(15)N)can deepen our understanding of forest ecosystem dynamics by indicating the long-term availability,cycling and sources of nitrogen(N).However,the rad... A knowledge of the tree-ring stable nitrogen isotope ratio(δ^(15)N)can deepen our understanding of forest ecosystem dynamics by indicating the long-term availability,cycling and sources of nitrogen(N).However,the radial mobility of N blurs the interannual variations in the long-term N records.Previous studies of the chemical extraction of tree rings before analysis had produced inconsistent results and it is still unclear whether it is necessary to pre-treat wood samples from specific tree species to remove soluble N compounds before determining theδ^(15)N values.We compared the effects of pre-treatment with organic solvents and hot ultrapure water on the N concentration andδ^(15)N of tree rings from endemic Qinghai spruce(Picea crassifolia)growing in the interior of the central Qilian Mountains,China,during the last 60 a.We assessed the effects of different preparation protocols on the removal of the labile N compounds and investigated the need to pre-treat wood samples before determining theδ^(15)N values of tree rings.Increasing trends of the tree-ring N concentration were consistently observed in both the extracted and unextracted wood samples.The total N removed by extraction with organic solvents was about 17.60%,with a significantly higher amount in the sapwood section(P<0.01).Theδ^(15)N values of tree rings decreased consistently from 1960 to 2019 in both the extracted and unextracted wood samples.Extraction with organic solvents increased theδ^(15)N values markedly by about 5.2‰and reduced the variations in theδ^(15)N series.However,extraction with hot ultrapure water had little effect,with only a slight decrease in theδ^(15)N values of about 0.5‰.Our results showed that the radial pattern in the inter-ring movement of N in Qinghai spruce was not minimized by extraction with either organic solvents or hot ultrapure water.It is unnecessary to conduct hot ultrapure water extraction for the wood samples from Qinghai spruce because of its negligible effect on the removal of the labile N.Theδ^(15)N variation trend of tree rings in the unextracted wood samples was not influenced by the heartwood-sapwood transition zone.We suggest that theδ^(15)N values of the unextracted wood samples of the climate-sensitive Qinghai spruce could be used to explore the ecophysiological dynamics while focusing on the long-term variations. 展开更多
关键词 tree rings stable nitrogen isotope ratio(δ^(15)N) nitrogen concentration solvent-extracted wood water-extracted wood wood pre-treatment Qinghai spruce Qilian Mountains
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Frontogenesis and Frontolysis of a Cold Filament Driven by the Cross-Filament Wind and Wave Fields Simulated by a Large Eddy Simulation 被引量:1
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作者 Guojing LI Dongxiao WANG +3 位作者 Changming DONG Jiayi PAN Yeqiang SHU Zhenqiu ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第3期509-528,共20页
The variations of the frontogenetic trend of a cold filament induced by the cross-filament wind and wave fields are studied by a non-hydrostatic large eddy simulation. Five cases with different strengths of wind and w... The variations of the frontogenetic trend of a cold filament induced by the cross-filament wind and wave fields are studied by a non-hydrostatic large eddy simulation. Five cases with different strengths of wind and wave fields are studied.The results show that the intense wind and wave fields further break the symmetries of submesoscale flow fields and suppress the levels of filament frontogenesis. The changes of secondary circulation directions—that is, the conversion between the convergence and divergence of the surface cross-filament currents with the downwelling and upwelling jets in the filament center—are associated with the inertial oscillation. The filament frontogenesis and frontolysis caused by the changes of secondary circulation directions may periodically sharpen and smooth the gradient of submesoscale flow fields.The lifecycle of the cold filament may include multiple stages of filament frontogenesis and frontolysis. 展开更多
关键词 cold filament FRONTOGENESIS FRONTOLYSIS large eddy simulation
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Pre-treatment to Enhance Biogas Yield from Pulp and Paper Mill Sludge
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作者 Karin Maria Granstrom Josefine Montelius 《Journal of Chemistry and Chemical Engineering》 2014年第8期825-833,共9页
The purpose of this work was to study the potential to enhance biogas production from pulp and paper mill sludge by the use of thermal pre-treatment in combination with chemical pre-treatment. Biogas from waste is a r... The purpose of this work was to study the potential to enhance biogas production from pulp and paper mill sludge by the use of thermal pre-treatment in combination with chemical pre-treatment. Biogas from waste is a renewable fuel with very low emissions during combustion. To further reduce the use of fossil fuels, more biogas substrates are necessary. Pulp and paper mill sludge is a large untapped reservoir of potential biogas. Pulp and paper mill sludge was collected from a mill that produces both pulp and paper and has a modified waste activated sludge system as part of its wastewater treatment. Pre-treatments were chosen heat (70 ~C or 140℃) combined with either acid (pH 2 or pH 4) or base (pH 9 or pH 11, obtained with Ca(OH)2 or NaOH). Biogas potential was tested by anaerobic digestion batch assays under mesophilic conditions. All pre-treatments were tested in six replicates. Biogas volume was measured with a gas-tight syringe and methane concentration was measured with a gas chromatograph. The methane yield from sludge subjected to thermal pre-treatment at 70℃ did not differ from the untreated sludge, but thermal pre-treatment at 140℃ had a positive effect. Within the 70℃ thermal pre-treatment group, the pH 2 acid was the most successful chemical pre-treatment, and Ca(OH)2 pH 9 had the least effect with no measurable improvement in methane yield. For the 140 ℃ thermal pre-treatment group, acid and NaOH impacted methane production negatively, while the Ca(OH)2-treated sludge did not differ from sludge with no chemical pre-treatment. In conclusion, thermal pre-treatment at 70℃ showed no effect, whereas, pre-treatment at 140℃ improved methane yield with 170%, and for this sludge additional, chemical pre-treatments are unnecessary. 展开更多
关键词 ANAEROBIC BIOGAS DIGESTION pre-treatment sludge.
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MIR1868 negatively regulates rice cold tolerance at both the seedling and booting stages 被引量:1
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作者 Yang Shen Xiaoxi Cai +7 位作者 Yan Wang Wanhong Li Dongpeng Li Hao Wu Weifeng Dong Bowei Jia Mingzhe Sun Xiaoli Sun 《The Crop Journal》 SCIE CSCD 2024年第2期375-383,共9页
Low temperature causes rice yield losses of up to 30%–40%,therefore increasing its cold tolerance is a breeding target.Few genes in rice are reported to confer cold tolerance at both the vegetative and reproductive s... Low temperature causes rice yield losses of up to 30%–40%,therefore increasing its cold tolerance is a breeding target.Few genes in rice are reported to confer cold tolerance at both the vegetative and reproductive stages.This study revealed a rice-specific 24-nt miRNA,miR1868,whose accumulation was suppressed by cold stress.Knockdown of MIR1868 increased seedling survival,pollen fertility,seed setting,and grain yield under cold stress,whereas its overexpression conferred the opposite phenotype.Knockdown of MIR1868 increased reactive oxygen species(ROS)scavenging and soluble sugar content under cold stress by increasing the expression of peroxidase genes and sugar metabolism genes,and its overexpression produced the opposite effect.Thus,MIR1868 negatively regulated rice cold tolerance via ROS scavenging and sugar accumulation. 展开更多
关键词 RICE cold tolerance MIRNA ROS scavenging Soluble sugar accumulation
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PHD17 acts as a target of miR1320 to negatively control cold tolerance via JA-activated signaling in rice 被引量:1
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作者 Yan Wang Yang Shen +6 位作者 Weifeng Dong Xiaoxi Cai Junkai Yang Yue Chen Bowei Jia Mingzhe Sun Xiaoli Sun 《The Crop Journal》 SCIE CSCD 2024年第5期1447-1458,共12页
Plant Homeo Domain(PHD)proteins are involved in diverse biological processes during plant growth.However,the regulation of PHD genes on rice cold stress response remains largely unknown.Here,we reported that PHD17 neg... Plant Homeo Domain(PHD)proteins are involved in diverse biological processes during plant growth.However,the regulation of PHD genes on rice cold stress response remains largely unknown.Here,we reported that PHD17 negatively regulated cold tolerance in rice seedlings as a cleavage target of miR1320.PHD17 expression was greatly induced by cold stress,and was down-regulated by miR1320 overexpression and up-regulated by miR1320 knockdown.Through 5'RACE and dual luciferase assays,we found that miR1320 targeted and cleaved the 3'UTR region of PHD17.PHD17 was a nuclearlocalized protein and acted as a transcriptional activator in yeast.PHD17 overexpression reduced cold tolerance of rice seedlings,while knockout of PHD17 increased cold tolerance,partially via the CBF cold signaling.By combining transcriptomic and physiological analyses,we demonstrated that PHD17 modulated ROS homeostasis and flavonoid accumulation under cold stress.K-means clustering analysis revealed that differentially expressed genes in PHD17 transgenic lines were significantly enriched in the jasmonic acid(JA)biosynthesis pathway,and expression of JA biosynthesis and signaling genes was verified to be affected by PHD17.Cold stress tests applied with MeJA or IBU(JA synthesis inhibitor)further suggested the involvement of PHD17 in JA-mediated cold signaling.Taken together,our results suggest that PHD17 acts downstream of miR1320 and negatively regulates cold tolerance of rice seedlings through JA-mediated signaling pathway. 展开更多
关键词 RICE cold tolerance PHD protein miR1320 JA signaling
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Endogenous serotonin induced by cold acclimation increases cold tolerance by reshaping the MEL/ROS/RNS redox network in Kandelia obovata
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作者 Junjian Li Huiyu Zhang +4 位作者 Danfei Yue Siyi Chen Yaxin Yin Chunfang Zheng Yan Chen 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第6期73-85,共13页
Cold stress severely limits the distribution of mangrove species worldwide and it remains unclear how mangroves respond and adapt to cold temperatures.In this study,we investigated the effects of cold acclimation and/... Cold stress severely limits the distribution of mangrove species worldwide and it remains unclear how mangroves respond and adapt to cold temperatures.In this study,we investigated the effects of cold acclimation and/or inhibition of serotonin levels on reactive oxygen species(ROS),reactive nitrogen species(RNS),melatonin(MEL)and serotonin(SER)accumulation during cold stress in Kandelia obovata.Morphologic observation and param-eter analysis revealed that cold acclimation mitigated the photoinhibition of photosystem I(PSI)and photosystem II(PSII),maintained optimal ROS and RNS redox homeosta-sis,and increased the contents of SER and MEL in leaves.This suggests that cold acclimation reshapes the MEL/ROS/RNS redox network.In particular,the tryptophan/tryptamine/Ser/N-acetylserotonin/MER pathway was identi-fied as a branch of the MEL synthesis pathway.Inhibition of endogenous SER exacerbated damage caused by cold stress,indicating the crosstalk of SER synthesis and cold acclima-tion.In this study,we report a coordinated regulation of cold stress by a complex defense network in K.obovata. 展开更多
关键词 cold acclimation SEROTONIN MELATONIN cold stress MANGROVES
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Effect of β-Glucan (Angel Yeast) Compared to a Placebo on Cold and Flu Incidence and Symptoms in an Adult Population—A Double Blind, Randomised Controlled Trial
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作者 David Briskey Haibo Zhang +1 位作者 Zhixian Chen Amanda Rao 《Food and Nutrition Sciences》 CAS 2024年第6期484-497,共14页
Background: 1-3, 1-6 β-glucan derived from Baker’s yeast (Saccharomyces cerevisiae) has been widely studied for its immune stimulatory capabilities and safety. Previous studies found β-glucan to have efficacy at re... Background: 1-3, 1-6 β-glucan derived from Baker’s yeast (Saccharomyces cerevisiae) has been widely studied for its immune stimulatory capabilities and safety. Previous studies found β-glucan to have efficacy at reducing incidence of URTIs as well as being a low risk for negative side effects. The current study aimed to examine the effects of yeast β-glucan (Angel Yeast) on cold and flu incidences and symptoms in healthy adults. Methods: Two hundred and thirty-one males and females aged 18 to 65 years old supplemented with either β-glucan or a placebo for 3-months. Participants completed a general health questionnaire every 4 weeks and in addition, if participants experienced any cold or flu symptoms, these were recorded daily (along with severity) until resolved or up to 2 weeks. Results: Supplementation with β-glucan reduced the self-reported severity of sore throats and improved sleep quality compared to the placebo group. Conclusions: Yeast β-glucan supplementation appears to be able to help reduce certain symptoms experienced during a cold or flu episode and is safe and well tolerated. 展开更多
关键词 BETA-GLUCAN cold FLU Baker’s Yeast
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The UDP-glycosyltransferase OsUGT706D2 positively regulates cold and submergence stress tolerance in rice
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作者 Qing Liu Lanlan Zhang +12 位作者 Shuwei Lyu Hang Yu Wenjie Huang Liqun Jiang Jing Zhang Bingrui Sun Xingxue Mao Pingli Chen Junlian Xing Wenfeng Chen Zhilan Fan Shijuan Yan Chen Li 《The Crop Journal》 SCIE CSCD 2024年第3期732-742,共11页
In a genome-wide association study,we identified a rice UDP-glycosyltransferase gene,OsUGT706D2,whose transcription was activated in response to cold and submergence stress and to exogenous abscisic acid(ABA).OsUGT706... In a genome-wide association study,we identified a rice UDP-glycosyltransferase gene,OsUGT706D2,whose transcription was activated in response to cold and submergence stress and to exogenous abscisic acid(ABA).OsUGT706D2 positively regulated the biosynthesis of tricin-4’-O-(syringyl alcohol)ether-7-O-glucoside at both the transcriptional and metabolic levels.OsUGT706D2 mediated cold and submergence tolerance by modulating the expression of stress-responsive genes as well as the abscisic acid(ABA)signaling pathway.Gain of function of OsUGT706D2 increased cold and submergence tolerance and loss of function of OsUGT706D2 reduced cold tolerance.ABA positively regulated OsUGT706D2-mediated cold tolerance but reduced submergence tolerance.These findings suggest the potential use of OsUGT706D2 for improving abiotic stress tolerance in rice. 展开更多
关键词 UDP-glycosyltransferase RICE cold tolerance Submergence tolerance ABA
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Boosting thermoelectric efficiency of Ag_(2)Se through cold sintering process with Ag nano-precipitate formation
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作者 Dejwikom Theprattanakorn Thanayut Kaewmaraya Supree Pinitsoontorn 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第12期2760-2769,共10页
Silver selenide(Ag_(2)Se)stands out as a promising thermoelectric(TE)material,particularly for applications near room temper-atures.This research presents a novel approach for the fabrication of bulk Ag_(2)Se samples ... Silver selenide(Ag_(2)Se)stands out as a promising thermoelectric(TE)material,particularly for applications near room temper-atures.This research presents a novel approach for the fabrication of bulk Ag_(2)Se samples at a relatively low temperature(170℃)using the cold sintering process(CSP)with AgNO_(3)solution as a transient liquid agent.The effect of AgNO_(3)addition during CSP on the micro-structure and TE properties was investigated.The results from phase,composition and microstructure analyses showed that the introduc-tion of AgNO_(3)solution induced the formation of Ag nano-precipitates within the Ag_(2)Se matrix.Although the nano-precipitates do not af-fect the phase and crystal structure of orthorhombicβ-Ag_(2)Se,they suppressed crystal growth,leading to reduced crystallite sizes.The samples containing Ag nano-precipitates also exhibited high porosity and low bulk density.Consequently,these effects contributed to sig-nificantly enhanced electrical conductivity and a slight decrease in the Seebeck coefficient when small Ag concentrations were incorpor-ated.This resulted in an improved average power factor from~1540μW·m^(−1)·K^(−2)for pure Ag_(2)Se to~1670μW·m^(−1)·K^(−2)for Ag_(2)Se with additional Ag precipitates.However,excessive Ag addition had a detrimental effect on the power factor.Furthermore,thermal conductiv-ity was effectively suppressed in Ag_(2)Se fabricated using AgNO_(3)-assisted CSP,attributed to enhanced phonon scattering at crystal inter-faces,pores,and Ag nano-precipitates.The highest figure-of-merit(zT)of 0.92 at 300 K was achieved for the Ag_(2)Se with 0.5wt%Ag dur-ing CSP fabrication,equivalent to>20%improvement compared to the controlled Ag_(2)Se without extra Ag solution.Thus,the process outlined in this study presents an effective strategy to tailor the microstructure of bulk Ag_(2)Se and enhance its TE performance at room temperature. 展开更多
关键词 THERMOELECTRIC silver selenide CHALCOGENIDE cold sintering process nano-precipitate
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Transcription factor CabHLH035 promotes cold resistance and homeostasis of reactive oxygen species in pepper
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作者 Huafeng Zhang Jiangbai Guo +7 位作者 Xiaoqing Chen Yunyun Zhou Yingping Pei Lang Chen Saeed ul Haq Mingke Zhang Haijun Gong Rugang Chen 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期823-836,共14页
Plant basic helix-loop-helix(bHLH)transcription factors(TFs)play central roles in various abiotic stresses.However,its role in plant cold resistance is largely unknown.Previously,we characterised CaNAC035 in pepper,wh... Plant basic helix-loop-helix(bHLH)transcription factors(TFs)play central roles in various abiotic stresses.However,its role in plant cold resistance is largely unknown.Previously,we characterised CaNAC035 in pepper,which positively regulates tolerance to cold,salt and drought stresses tolerance.Here,we identified CabHLH035,a CaNAC035-interacting protein in pepper.To explore its functions in cold stress tolerance,we silenced the gene in pepper via virus-induced gene silencing(VIGS)and overexpressed the gene in Arabidopsis.The results showed that CabHLH035 expression was induced by cold treatment,and silencing of CabHLH035 decreased cold stress tolerance.Conversely,overexpression of CabHLH035 in Arabidopsis increased cold stress tolerance.To investigate homologs genes of C-repeat binding factor(CBF)pathway proteins and reactive oxygen species(ROS)marker gene expression blocking by CabHLH035,we performed yeast one-hybrid(Y1H),dual luciferase and electrophoretic mobility shift assay experiments.The results showed that CabHLH035 bound to the region upstream of the CaCBF1A and CaAPX promoters.Additionally,CaCBF1A bound to the CaDHN4 promoter.Taken together,our results showed that CabHLH035 plays a crucial role in cold stress tolerance and its potential as a target for breeding cold-resistant crops.The findings provide a basis for studying the functions and regulatory network of cold stress tolerance in pepper. 展开更多
关键词 PEPPER CabHLH035 SILENCING Overexpression VIGS cold tolerance
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Extreme Antarctic Cold of Late Winter 2023
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作者 Anastasia J.TOMANEK David E.MIKOLAJCZYK +7 位作者 Matthew A.LAZZARA Stefano DI BATTISTA Minghu DING Mariana FONTOLAN LITELL David H.BROMWICH Taylor P.NORTON Linda M.KELLER Lee J.WELHOUSE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第10期1873-1880,共8页
Extreme cold temperatures were observed in July and August 2023,coinciding with the WINFLY(winter fly-in)period of mid to late August into September 2023,meaning aircraft operations into McMurdo Station and Phoenix Ai... Extreme cold temperatures were observed in July and August 2023,coinciding with the WINFLY(winter fly-in)period of mid to late August into September 2023,meaning aircraft operations into McMurdo Station and Phoenix Airfield were adversely impacted.Specifically,with temperatures below−50℃,safe flight operation was not possible because of the risk of failing hydraulics and fuel turning to gel onboard the aircraft.The cold temperatures were measured across a broad area of the Antarctic,from East Antarctica toward the Ross Ice Shelf,and stretching across West Antarctica to the Antarctic Peninsula.A review of automatic weather station measurements and staffed station observations revealed a series of sites recording new record low temperatures.Four separate cold phases were identified,each a few days in duration and occurring from mid-July to the end of August 2023.A brief analysis of 500-hPa geopotential height anomalies shows how the mid-tropospheric atmospheric environment evolves in relation to these extreme cold temperatures.The monthly 500-hPa geopotential height anomalies show strong negative anomalies in August.Examination of composite geopotential height anomalies during each of the four cold phases suggests various factors leading to cold temperatures,including both southerly off-content flow and calm atmospheric conditions.Understanding the atmospheric environment that leads to such extreme cold temperatures can improve prediction of such events and benefit Antarctic operations and the study of Antarctic meteorology and climatology. 展开更多
关键词 ANTARCTICA extreme cold temperature automatic weather station networks
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