期刊文献+
共找到177篇文章
< 1 2 9 >
每页显示 20 50 100
Volatile Solid and Bury Period Influence on Odorous Material Production in Simulating Landfill Treatment
1
作者 Peng Lu yuanyuan zhang +5 位作者 Linan Xing Ying Wang Hong Lu Dongbei Yue Wei Cheng Jin Liu 《Journal of Geoscience and Environment Protection》 2024年第1期120-129,共10页
Odor pollution in landfill area has attracted more social attention in China. It is very important to control the generation of odor pollutants in situ. Analyzing odorous materials production form buried waste, simula... Odor pollution in landfill area has attracted more social attention in China. It is very important to control the generation of odor pollutants in situ. Analyzing odorous materials production form buried waste, simulated columns of different volatile solid (VS) content and different buried period waste were designed. Gas compounds produced from the columns were collected and analyzed by comprehensive two-dimensional gas chromatography (GC × GC) method. It has remarkable relationship between VS content and concentrations of odorous material. When VS content more than 40%, the total amount of odorous compounds increases remarkably. It can be inferred that reduced VS content of original waste may effective decreasing odorous materials production in landfill area. The old rubbish produced more odorous compounds than that of fresh one in simulated columns. 展开更多
关键词 Volatile Solid Odorous Material Bury Period
下载PDF
“无限兜底”:县域政府的责任扩张及其形成机制——基于M省F县城市广场项目的案例追踪
2
作者 张园园 赵一航 《公共行政评论》 北大核心 2024年第3期140-158,199,共20页
传统县域政府的责任描述集中在结构激励和主体行动两个维度,揭示了县域政府相对固定的责任权限。然而,随着城市化与行政问责的同步推进,县域政府的职责在多重外部环境的影响下不断扩展。M省F县的城市广场建设经历了“投资——烂尾——... 传统县域政府的责任描述集中在结构激励和主体行动两个维度,揭示了县域政府相对固定的责任权限。然而,随着城市化与行政问责的同步推进,县域政府的职责在多重外部环境的影响下不断扩展。M省F县的城市广场建设经历了“投资——烂尾——重找投资人——再烂尾”的过程,县域政府在此过程中经过多轮博弈最终无奈“兜底”了该项目。研究发现,县域政府在压力型体制和“维稳机制”的双重作用下,被动扩展了其行政权责边界,并逐步参与到市场和社会活动中;不确定的市场环境会增加县域政府的参与意愿,从而强化其经营统合的偏好;经营统合的不可逆以及公众的习惯性依附使县域政府陷入“无限兜底”的境地。面对当前县域政府风险兜底的困境,需要适当疏解压力型体制对“维稳机制”的滥用,减缓地区横向比较的压力,追加项目的长期责任制,提供更为积极的风险防控措施。 展开更多
关键词 县域政府 “无限兜底” 责任边界 基层治理
下载PDF
J-shaped association between dietary thiamine intake and the risk of cognitive decline in cognitively healthy,older Chinese individuals
3
作者 Chengzhang Liu Qiguo Meng +7 位作者 Yuanxiu Wei Xinyue Su yuanyuan zhang Panpan He Chun Zhou Mengyi Liu Ziliang Ye Xianhui Qin 《General Psychiatry》 CSCD 2024年第1期44-52,共9页
Background The prospective association of dietary thiamine intake with the risk of cognitive decline among the general older adults remains uncertain.Aims To investigate the association between dietary thiamine intake... Background The prospective association of dietary thiamine intake with the risk of cognitive decline among the general older adults remains uncertain.Aims To investigate the association between dietary thiamine intake and cognitive decline in cognitively healthy,older Chinese individuals.Methods The study included a total of 3106 participants capable of completing repeated cognitive function tests.Dietary nutrient intake information was collected through 3-day dietary recalls and using a 3-day food-weighed method to assess cooking oil and condiment consumption.Cognitive decline was defined as the 5-year decline rate in global or composite cognitive scores based on a subset of items from the Telephone Interview for Cognitive Status-modified.Results The median follow-up duration was 5.9 years.There was a J-shaped relationship between dietary thiamine intake and the 5-year decline rate in global and composite cognitive scores,with an inflection point of 0.68 mg/day(95%confidence interval(Cl):0.56 to 0.80)and a minimal risk at 0.60-1.00 mg/day of dietary thiamine intake.Before the inflection point,thiamine intake was not significantly associated with cognitive decline.Beyond the inflection point,each unit increase in thiamine intake(mg/day)was associated with a significant decrease of 4.24(95%Cl:2.22 to 6.27)points in the global score and 0.49(95%Cl:0.23 to 0.76)standard units in the composite score within 5 years.A stronger positive association between thiamine intake and cognitive decline was observed in those with hypertension,obesity and those who were non-smokers(all p<0.05).Conclusions This study revealed a J-shaped association between dietary thiamine intake and cognitive decline in cognitively healthy,older Chinese individuals,with an inflection point at 0.68 mg/day and a minimal risk at 0.60-1.00 mg/day of dietary thiamine intake. 展开更多
关键词 INTAKE shaped cognitive
下载PDF
A rapid and visual detection method for Crimean-Congo hemorrhagic fever virus by targeting S gene
4
作者 Xingqi Liu Zengguo Cao +8 位作者 Boyi Li Pei Huang Yujie Bai Jingbo Huang Zanheng Huang yuanyuan zhang yuanyuan Li Haili zhang Hualei Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期2149-2153,共5页
Crimean-Congo hemorrhagic fever(CCHF)is a zoonotic disease caused by the CCHF virus(CCHFV),which is primarily transmitted by ticks(Lorenzo Juanes et al.2023).It is an emerging disease that occurs sporadically in Afric... Crimean-Congo hemorrhagic fever(CCHF)is a zoonotic disease caused by the CCHF virus(CCHFV),which is primarily transmitted by ticks(Lorenzo Juanes et al.2023).It is an emerging disease that occurs sporadically in Africa,Asia,and Europe,with a high morbidity and mortality rate,as high as 30%in humans(Ceylan et al.2013).CCHFV,belonging to genus Nairovirus,family Bunyaviridae,was first identified in the Congo in the 1960s. 展开更多
关键词 HEMORRHAGIC FEVER
下载PDF
The Impact of Optimizing Details in the Operating Room on the Level of Knowledge, Attitude, and Practice of Hospital Infection Prevention and Control by Surgeons, as Well as the Effectiveness of Infection Control
5
作者 yuanyuan zhang 《Surgical Science》 2024年第7期421-429,共9页
Objective: This paper aims to explore the impact of optimizing details in the operating room on the level of knowledge, attitude, and practice of hospital infection prevention and control by surgeons, as well as the e... Objective: This paper aims to explore the impact of optimizing details in the operating room on the level of knowledge, attitude, and practice of hospital infection prevention and control by surgeons, as well as the effectiveness of infection control. Methods: From January 2022 to June 2023, a total of 120 patients were screened and randomly divided into a control group (routine care and hospital infection management) and a study group (optimizing details in the operating room). Results: Significant differences were found between the two groups in the data of surgeons’ level of knowledge, attitude, and practice in hospital infection prevention and control, infection rates, and nursing satisfaction, with the study group showing better results (P Conclusion: The use of optimizing details in the operating room among surgeons can effectively improve surgeons’ level of knowledge, attitude, and practice in hospital infection prevention and control, reduce infection occurrence, and is worth promoting. 展开更多
关键词 Optimizing Details in the Operating Room Infection Level of Knowledge ATTITUDE and Practice Infection Control
下载PDF
聚醚醚酮/聚醚酰亚胺合金的热学性能与力学性能 被引量:1
6
作者 莫小龙 张园园 +2 位作者 李元庆 黄培 付绍云 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2023年第5期118-124,共7页
通过熔融共混和注塑成型的方法制备了不同质量比的聚醚醚酮/聚醚酰亚胺(PEEK/PEI)合金,确定了各种质量比下时的最佳加工温度。采用热重分析、差示扫描量热分析、动态力学热分析和拉伸、三点弯曲的性能表征方法,研究了PEEK/PEI共混合金... 通过熔融共混和注塑成型的方法制备了不同质量比的聚醚醚酮/聚醚酰亚胺(PEEK/PEI)合金,确定了各种质量比下时的最佳加工温度。采用热重分析、差示扫描量热分析、动态力学热分析和拉伸、三点弯曲的性能表征方法,研究了PEEK/PEI共混合金的热学和力学性能随PEEK/PEI质量比的变化趋势。结果表明,各组分比的PEEK/PEI合金均具有良好的热稳定性;随着PEEK含量增加,合金结晶度呈现上升的趋势,而玻璃化转变温度不断下降;室温时,PEEK含量对PEEK/PEI共混物的力学性能影响较弱;当测试温度稍低于PEEK玻璃化转变温度时,其力学性能随着PEEK含量的增加表现出降低的趋势;当测试温度在PEEK与PEI玻璃化转变温度之间时,合金的力学性能随着PEEK含量的增加先下降再上升。最后,基于随机森林法量化了合金质量比及热性能参数对PEEK/PEI合金力学性能的贡献程度。 展开更多
关键词 聚醚醚酮 聚醚酰亚胺 共混物 常温高温力学性能
下载PDF
Ph-C≡C-Cu基新型功能材料的结构-性质-效能关系探究 被引量:1
7
作者 蒋海英 穆玥如 +4 位作者 张媛媛 孙雪 王云侠 郭慧林 岳可芬 《大学化学》 CAS 2023年第11期206-215,共10页
为了培养本科生综合运用所学知识分析和解决问题的能力,本文基于最新研究成果,深入挖掘其中所涉及的本科基础化学知识,设计了探究苯乙炔铜(Ph-C≡C-Cu)基新型功能材料结构-性质-效能关系的综合实验。本实验通过光热合成法制备了三种含... 为了培养本科生综合运用所学知识分析和解决问题的能力,本文基于最新研究成果,深入挖掘其中所涉及的本科基础化学知识,设计了探究苯乙炔铜(Ph-C≡C-Cu)基新型功能材料结构-性质-效能关系的综合实验。本实验通过光热合成法制备了三种含不同官能团的Ph-C≡C-Cu基新型功能材料,利用红外(FT-IR)光谱、紫外-可见吸收(UV-Vis Abs)光谱和稳态水接触角表征了其结构和相关物理化学性质,并研究了其结构对于有机染料甲基橙(MO)的吸附和降解效能的影响。作为本科生基础教学实验,本实验考查了学生对有机化学中不同官能团的电子效应和物理化学中液-固界面相互作用、固体在溶液中的吸附、催化反应动力学以及反应级数的判定等知识的理解、掌握和应用。通过进一步总结与讨论Ph-C≡C-Cu基新型功能材料的结构-性质-效能关系,启发并引导学生以实际问题为导向,根据所学理论和知识,从源头上出发,对功能材料的结构进行设计,培养了本科生的逆向思维方式,提升了本科生理论与实践相结合的能力。 展开更多
关键词 新型功能材料 Ph-C≡C-Cu 结构-性质-效能关系 逆向思维方式
下载PDF
整合与适应:巡游出租车司机的数字平台驯化实践 被引量:2
8
作者 张媛媛 冯锐 《全球传媒学刊》 2023年第5期24-38,共15页
伴随着网络预约出行平台和传统巡游出租车的融合,数字平台成为一种外来技术开始进入巡游出租车司机的日常劳动过程。本研究基于驯化理论框架,对67位巡游出租车司机进行了观察和半结构化访谈,并对巡游出租车司机的3个社交群聊进行了参与... 伴随着网络预约出行平台和传统巡游出租车的融合,数字平台成为一种外来技术开始进入巡游出租车司机的日常劳动过程。本研究基于驯化理论框架,对67位巡游出租车司机进行了观察和半结构化访谈,并对巡游出租车司机的3个社交群聊进行了参与式观察,探究了处于平台经济形态与传统工作状态交界处的司机群体对数字平台的驯化过程。研究发现,巡游出租车司机借助技术想象与意义建构勾连接入动机,调整工作时间与空间以完成技术的物质嵌入,通过知识共享与情感共鸣实现身份共同体的重塑。巡游出租车司机对数字平台的驯化实践呈现出技术融入生活过程中的整合与适应特征,是对经典劳动过程理论中二元对立框架的回应与延展。 展开更多
关键词 驯化理论 数字平台 巡游出租车司机 媒介化实践
下载PDF
Fecal microbiota dynamics and its relationship to diarrhea and health in dairy calves 被引量:2
9
作者 Hongwei Chen Yalu Liu +4 位作者 Kailang Huang Bin Yang yuanyuan zhang Zhongtang Yu Jiakun Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第1期358-377,共20页
Background:Diarrhea is a major cause of morbidity and mortality in young calves,resulting in considerable economic loss for dairy farms.To determine if some gut microbes might have resistance to dysbiotic process with... Background:Diarrhea is a major cause of morbidity and mortality in young calves,resulting in considerable economic loss for dairy farms.To determine if some gut microbes might have resistance to dysbiotic process with calf diarrhea by dictating the microbial co-occurrence patterns from birth to post-weaning,we examined the dynamic development of the gut microbiota and diarrhea status using two animal trials,with the first trial having 14 Holstein dairy calves whose fecal samples were collected 18 times over 78 d from birth to 15 d post-weaning and the second trial having 43 Holstein dairy calves whose fecal samples were collected daily from 8 to 18 days of age corresponding to the first diarrhea peak of trial 1.Results:Metataxonomic analysis of the fecal microbiota showed that the development of gut microbiota had three age periods with birth and weaning as the separatrices.Two diarrhea peaks were observed during the transition of the three age periods.Fusobacteriaceae was identified as a diarrhea-associated taxon both in the early stage and during weaning,and Clostridium_sensu_stricto_1 was another increased genus among diarrheic calves in the early stage.In the neonatal calves,Prevotella_2(ASV4 and ASV26),Prevotella_9(ASV43),and Alloprevotella(ASV14)were negatively associated with Clostridium_sensu_stricto_1(ASV48),the keystone taxa of the diarrhea-phase module.During weaning,unclassified Muribaculaceae(ASV28 and ASV44),UBA1819(ASV151),Barnesiella(ASV497),and Ruminococcaceae_UCG-005(ASV254)were identified being associated with non-diarrheic status,and they aggregated in the non-diarrhea module of co-occurrence patterns wherein unclassified Muribaculaceae(ASV28)and Barnesiella(ASV497)had a direct negative relationship with the members of the diarrhea module.Conclusions:Taken together,our results suggest that the dynamic successions of calf gut microbiota and the interactions among some bacteria could influence calf diarrhea,and some species of Prevotella might be the core microbiota in both neonatal and weaning calves,while species of Muribaculaceae might be the core microbiota in weaning calves for preventing calf diarrhea.Some ASVs affiliated with Prevotella_2(ASV4 and ASV26),Prevotella_9(ASV43),Alloprevotella(AVS14),unclassified Muribaculaceae(ASV28 and ASV44),UBA1819(ASV151),Ruminococcaceae_UCG-005(ASV254),and Barnesiella(ASV497)might be proper probiotics for preventing calf diarrhea whereas Clostridium_sensu_stricto_1(ASV48)might be the biomarker for diarrhea risk in specific commercial farms. 展开更多
关键词 Calf diarrhea Co-occurrence pattern Dynamic development Fecal microbiota
下载PDF
Exploring the anti-aging effects of chlorogenic acid and the underlying mechanisms based on a Caenorhabditis elegans model 被引量:2
10
作者 Yuqian Yang Xu Chen +7 位作者 Danyang Ye Chuanyu Wei Xinxin Pang Chuchu Kong Yongsheng Fang Hongliu Yang yuanyuan zhang Yonggang Liu 《Journal of Traditional Chinese Medical Sciences》 CAS 2023年第2期208-217,共10页
Objective:To explore the anti-aging effects of chlorogenic acid(CGA)and the underlying mechanisms based on a Caenorhabditis elegans(C.elegans)model.Methods:The anti-agingactivityofCGAwasstudied basedon thebodylength,e... Objective:To explore the anti-aging effects of chlorogenic acid(CGA)and the underlying mechanisms based on a Caenorhabditis elegans(C.elegans)model.Methods:The anti-agingactivityofCGAwasstudied basedon thebodylength,exercisebehavior,lipofuscin content,antioxidative stress ability,swallowing frequency,body-bending frequency,and head-swinging ability of C.elegans.Through DAF-16 nuclear translocation and SOD-3-GFP fluorescence experiments,the effects of CGA on ROS levels,antioxidant enzyme activities,MDA content,mutant-strain lifespan,and anti-aging molecular signaling pathways were explored,as well as the underlying mechanisms.Results:CGA improved multiple indices of the nematode:body length was increased(all P<0.001),head-swing frequency and body-bending frequency were increased(all P<0.05),nematode longevity was prolonged(P=0.0021),lipofuscin deposition in nematodes was slowed down(all P<0.001),the chemotaxis index was improved(P=0.0012),ROS levels were reduced(all P<.001),and SOD activity and MDA content were reduced(SOD:P=0.0017 between the low-concentration group and the control group,P<.001 between the high-concentration and medium-concentration groups and the control group;MDA:P=0.0135 between the low-concentration group and the control group,and P<0.001 between the high-concentration and medium-concentration groups and the control group).In addition,CGA also activated the DAF-16 transcription factor,promoted DAF-16 nuclear translocation under oxidative stress conditions(both P<0.001 between the high-concentration and medium-concentration groups and the control group),and increased SOD-3 gene expression in nematodes(all P<0.001).Conclusion:CGA plays an anti-aging role in C.elegans.The underlying mechanisms include activation of the insulin/IGF-1 signaling pathway and enhancement of DAF-16 activity.This study lays a foundation for further research into the anti-aging effects of CGA. 展开更多
关键词 Chlorogenic acid Caenorhabditis elegans Antioxidant activity ANTI-AGING DAF-16
下载PDF
具有电子转移路径的金属化氮化碳选择性再生NADH和光酶偶联CO_(2)还原
11
作者 张鹏业 董文锦 +7 位作者 张媛媛 赵立楠 苑华磊 王传军 王文硕 王含笑 张洪禹 刘健 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第11期188-198,共11页
将CO_(2)转化为燃料和化学品被认为是缓解能源危机的一种有效策略.受自然光合作用的启发,光酶偶联结合了光催化和酶催化的优点,在绿色生物制造中具有较好的应用前景.铑(Rh)络合物是选择性再生还原型烟酰胺腺嘌呤二核苷酸(M-NADH)的关键... 将CO_(2)转化为燃料和化学品被认为是缓解能源危机的一种有效策略.受自然光合作用的启发,光酶偶联结合了光催化和酶催化的优点,在绿色生物制造中具有较好的应用前景.铑(Rh)络合物是选择性再生还原型烟酰胺腺嘌呤二核苷酸(M-NADH)的关键介体,其固定化可以提高体系的可持续性,并有效缩短电子传递路径,因而受到广泛关注.本文制备了联吡啶功能化的金属化氮化碳(PCNRhbpy_(4)),用于光酶偶联催化CO_(2)还原.首先以双氰胺为前驱体,通过两步退火法制备氮化碳(PCN),再与5,5’-二氨基-2,2’-联吡啶(DABP)进一步热缩合,然后锚定[Cp*RhCl2]2获得PCNRhbpy4,并通过透射电镜、扫描电镜、粉末X射线衍射、紫外可见光吸收光谱、瞬态表面光电压和荧光发射光谱等进行表征.结果表明,合成的PCNRhbpy4材料具有掺杂石墨烯结构,且通过残余的末端联吡啶结构均匀地固定了Rh络合物.以PCNRhbpy4作为光催化剂实现了1,4-NADH的100%选择性再生,并在2.0 min内实现了80%的NADH再生.进一步耦合固定在疏水膜上的甲酸脱氢酶,可以有效地将CO_(2)还原为甲酸盐,48 h内甲酸盐浓度达到7 mmol L^(-1).此外,光催化剂的循环实验结果表明,PCNRhbpy4具有较高的稳定性.反应机理研究结果表明,光生电子经N-掺杂石墨烯传递到Rh活性位点,并结合溶液中的质子,随后氢负离子通过环滑移机制传递到NAD+,高选择性再生1,4-NADH.综上,本文为Rh的固定化开辟了一条新路径,实现了光酶催化CO_(2)还原,为光酶催化在绿色生物制造的实际应用提供参考. 展开更多
关键词 仿生金属化 NADH再生 光酶偶联催化 CO_(2)还原 电荷转移
下载PDF
Surface reconstruction of Se-doped NiS_(2) enables high-efficiency oxygen evolution reaction
12
作者 Mengxin Chen yuanyuan zhang +5 位作者 Ran Wang Bin zhang Bo Song Yanchao Guan Siwei Li Ping Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第9期173-180,共8页
Surface reconstruction of electrocatalysts has been widely witnessed during the electrochemical processes.Here,NiS_(2),NiSe_(2), and Se doped NiS_(2)(Se-NiS_(2)) are fabricated for oxygen evolution reaction(OER) throu... Surface reconstruction of electrocatalysts has been widely witnessed during the electrochemical processes.Here,NiS_(2),NiSe_(2), and Se doped NiS_(2)(Se-NiS_(2)) are fabricated for oxygen evolution reaction(OER) through a mild sulfuration and/or selenylation process of Ni(OH)_(2) supported on carbon cloth(CC).Through careful in-situ Raman spectroscopy and ex-situ X-ray photoelectron spectroscopy,surface reconstruction of NiS_(2),NiSe_(2),and Se-NiS_(2) during the OER process has been revealed.A potentialdependent study shows that Se-NiS_(2) undergoes surface evolution at lower potentials and requires the lowest potential for conversion to NiOOH as a highly OER-active species,accompanied by the leaching of SO_(4)^(2-) and SeO_(4)^(2-) that can again be adsorbed on the catalyst surface to enhance the catalytic activity.Density functional theory(DFT) calculations confirm that Se-NiS_(2) is more susceptible to surface oxidation through the OER process.Therefore,Se-NiS_(2) exhibits outstanding OER activity and stability in alkaline conditions,requiring an overpotential of 343 mV at a current density of 50 mA cm^(-2).A novel insight is provided by our work in understanding the surface reconstruction and electrocatalytic mechanism of Ni-based chalcogenides. 展开更多
关键词 Oxygen evolution reaction Se-NiS_(2) In-situ Raman spectroscopy Anion leaching Surface reconstruction
下载PDF
Magnetic field‐enhanced water splitting enabled by bifunctional molybdenum‐doped nickel sulfide on nickel foam
13
作者 yuanyuan zhang Mengxin Chen +5 位作者 Ping Guo Yunchen Du Bo Song Xianjie Wang Zaixing Jiang Ping Xu 《Carbon Energy》 SCIE EI CAS CSCD 2023年第10期50-63,共14页
Herein,we report bifunctional molybdenum-doped nickel sulfide on nickel foam(Mo-NiS_(x)/NF)for magnetic field-enhanced overall water splitting under alkaline conditions.Proper doping of Mo can lead to optimization of ... Herein,we report bifunctional molybdenum-doped nickel sulfide on nickel foam(Mo-NiS_(x)/NF)for magnetic field-enhanced overall water splitting under alkaline conditions.Proper doping of Mo can lead to optimization of the electronic structure of NiS_(x),which accelerates the dissociation of H2O and the adsorption of OH−in the hydrogen evolution reaction(HER)and the oxygen evolution reaction(OER)processes,respectively.In addition,the magnetically active Mo-NiS_(x)/NF can further enhance the HER and OER activity under an applied magnetic field due to the magnetoresistance effect and the ferromagnetic(FM)exchange-field penetration effect.As a result,Mo-NiS_(x)/NF requires low overpotentials of 307 mV at 50mA cm^(−2)(for OER)and 136 mV at 10mA cm^(−2)(for HER)under a magnetic field of 10000 G.Furthermore,the electrolytic cell constructed by the bifunctional Mo-NiS_(x)/NFs as both the cathode and the anode shows a low cell voltage of 1.594 V at 10 mA cm^(−2)with optimal stability over 60 h under the magnetic field.Simultaneous enhancement of the HER and OER processes by an external magnetic field through rational design of electrocatalysts might be promising for overall water splitting applications. 展开更多
关键词 electron density modulation FM exchange‐field penetration effect magnetic field magnetoresistance effect water splitting
下载PDF
Brittle culm 25, which encodes an UDP-xylose synthase, affects cell wall properties in rice
14
作者 Siliang Xu Mengchen zhang +12 位作者 Junhua Ye Dongxiu Hu yuanyuan zhang Zhen Li Junrong Liu Yanfei Sun Shan Wang Xiaoping Yuan Yue Feng Qun Xu Xinghua Wei Dali Zeng Yaolong Yang 《The Crop Journal》 SCIE CSCD 2023年第3期733-743,共11页
Because plant mechanical strength influences plant growth and development,the regulatory mechanisms underlying cell-wall synthesis deserve investigation.Rice mutants are useful for such research.We have identified a n... Because plant mechanical strength influences plant growth and development,the regulatory mechanisms underlying cell-wall synthesis deserve investigation.Rice mutants are useful for such research.We have identified a novel brittle culm 25(bc25)mutant with reduced growth and partial sterility.BC25 encodes an UDP-glucuronic acid decarboxylase involved in cellulose synthesis and belongs to the UXS family.A single-nucleotide mutation in BC25 accounts for its altered cell morphology and cellwall composition.Transmission electron microscopy analysis showed that the thickness of the secondary cell wall was reduced in bc25.Monosaccharide analysis revealed significant increases in content of rhamnose and arabinose but not of other monosaccharides,indicating that BC25 was involved in xylose synthesis with some level of functional redundancy.Enzymatic assays suggested that BC25 functions with high activity to interconvert UDP-glucuronic acid(UDP-Glc A)and UDP-xylose.GUS staining showed that BC25 was ubiquitously expressed with higher expression in culm,root and sheath,in agreement with that shown by quantitative real-time(q RT)-PCR.RNA-seq further suggested that BC25 is involved in sugar metabolism.We conclude that BC25 strongly influences rice cell wall formation. 展开更多
关键词 Brittle culm Mechanical strength UDP-xylose Cell wall RICE
下载PDF
Recent advances of transition-metal metaphosphates for efficient electrocatalytic water splitting
15
作者 yuanyuan zhang Jie Wu +4 位作者 Bingrong Guo Haohao Huo Siqi Niu Siwei Li Ping Xu 《Carbon Energy》 SCIE EI CAS CSCD 2023年第12期153-174,共22页
Sustainable production of H2 through electrochemical water splitting is of great importance in the foreseeable future.Transition-metal metaphosphates(TMMPs)have a three-dimensional(3D)open-framework structure and a hi... Sustainable production of H2 through electrochemical water splitting is of great importance in the foreseeable future.Transition-metal metaphosphates(TMMPs)have a three-dimensional(3D)open-framework structure and a high content of P(which exists as PO3-),and therefore have been recognized as highly efficient catalysts for oxygen evolution reaction(OER)and the bottleneck of electrochemical water splitting.Furthermore,TMMPs can also contribute to hydrogen evolution reaction(HER)in alkaline and neutral media by facilitating water dissociation,and thus,overall water splitting can be achieved using this kind of material.In this timely review,we summarize the recent advances in the synthesis of TMMPs and their applications in OER and HER.We present a brief introduction of the structure and synthetic strategies of TMMPs in the first two parts.Then,we review the latest progress made in research on TMMPs as OER,HER,and overall water-splitting electrocatalysts.In this part,the intrinsic activity of TMMPs as well as the current strategy for improving the catalytic activity will be discussed systematically.Finally,we present the future opportunities and the remaining challenges for the application of TMMPs in the electrocatalysis field. 展开更多
关键词 ELECTROCATALYSIS synthetic strategies transition-metal metaphosphates water splitting
下载PDF
DNA methylation mediated by RdDM pathway and demethylation affects furanone accumulation through regulation of QUINONE OXIDOREDUCTASE in strawberry
16
作者 Yunduan Li Yanna Shi +9 位作者 Yichen Li Jiao Lu Yunfan Sun yuanyuan zhang Wenbo Chen Xiaofang Yang Donald Grierson Zhaobo Lang Guihua Jiang Kunsong Chen 《Horticulture Research》 SCIE CSCD 2023年第8期170-182,共13页
Recently,increasing evidence suggests that DNA methylation plays a crucial role in fruit ripening.However,the role of DNA methylation in regulating specific traits,such as flavor,remains unclear.Here,we report a role ... Recently,increasing evidence suggests that DNA methylation plays a crucial role in fruit ripening.However,the role of DNA methylation in regulating specific traits,such as flavor,remains unclear.Here,we report a role of DNA methylation in affecting furanone biosynthesis in strawberry.Strawberry quinone oxidoreductase(FaQR)is a key enzyme in furanone biosynthesis.There are four FaQR homologs in strawberry cultivar‘Yuexin’,and one of them,FaQR3,contributes∼50%of FaQR transcripts,indicating a major role of FaQR3 in furanone biosynthesis.Through characterization of levels of DNA methylation and FaQR3 transcript and furanone contents during fruit ripening and after the application of DNA methylation inhibitor,we found that the DNA methylation level of the FaQR3 promoter was negatively correlated with FaQR3 expression and furanone accumulation,suggesting that DNA methylation may be involved in furanone biosynthesis through adjusting FaQR3 expression,and responded to different temperatures consistently.In addition,transient expression of a gene in the RNA-directed DNA methylation(RdDM)pathway,FaAGO4,and enrichment analysis of the 24-nucleotide siRNAs suggested that DNA methylation in the FaQR3 promoter is mediated by the RdDM pathway.Transient RNA interference(RNAi)of FaDML indicated that the demethylation pathway may be involved in regulating furanone accumulation.These findings provide new insights into the role of DNA methylation and demethylation in affecting flavor quality in strawberry during fruit ripening. 展开更多
关键词 STRAW FURAN transient
下载PDF
Discussion on the Application of Operating Room Nursing in Patients with Uterine Fibroids and Diabetes
17
作者 Yuanmeng Zhu yuanyuan zhang 《Journal of Cancer Therapy》 2023年第12期443-450,共8页
Objective: To analyze the application value of surgical nursing in patients with uterine fibroids and diabetes. Method: Sixty diabetic patients who agreed to undergo surgery for uterine fibroids at the Sun Yat-sen Uni... Objective: To analyze the application value of surgical nursing in patients with uterine fibroids and diabetes. Method: Sixty diabetic patients who agreed to undergo surgery for uterine fibroids at the Sun Yat-sen University Cancer Center from January 2021 to May 2022 were randomly selected as the study subjects. According to criteria such as number of patients, age, nursing methods, and treatment methods, the patients were evenly divided into an observation group and a control group. The control group received routine nursing measures, while the observation group received focused surgical nursing measures based on the routine ones. The blood glucose and blood lipid metabolism status, the incidence of adverse reactions, and nursing satisfaction were compared between the two groups. Results: The blood glucose and blood lipid metabolism status of the observation group were safer than those of the control group (P < 0.05). The observation group had advantages in terms of the incidence of adverse reactions and nursing satisfaction compared to the control group (P Conclusion: Systematic surgical nursing for patients with uterine fibroids and diabetes during surgery can help patients control their blood glucose and blood lipid metabolism status, reduce the incidence of adverse reactions, and improve the patient’s experience during the treatment stage. 展开更多
关键词 Uterine Fibroids DIABETES CARE SAFETY
下载PDF
Influence of Robot-Assisted Tumor Surgery Nursing on Patient Rehabilitation in Operating Room and Discussion on Nursing Strategies
18
作者 yuanyuan zhang 《Journal of Cancer Therapy》 2023年第9期367-372,共6页
Objective: To evaluate the effect of operating room nursing on the outcome of patients undergoing robot-assisted tumor surgery. Methods: This research starts from October 2021 to October 2022. The number of patients w... Objective: To evaluate the effect of operating room nursing on the outcome of patients undergoing robot-assisted tumor surgery. Methods: This research starts from October 2021 to October 2022. The number of patients with robot-assisted tumor surgery included in our hospital is 769. The patients are treated in the operating room, and the prognosis of the patients is summarized. Results: The intraoperative blood loss in patients undergoing robot-assisted tumor surgery was (57.51 ± 12.01) ml;the operation time was (3.57 ± 0.66) h;and the hospital stay was (6.04 ± 0.53) d. There were 21 cases of complications after robot-assisted tumor surgery, accounting for 2.73%. After surgery, all robot-assisted tumor surgery patients recovered and were discharged smoothly after being checked by doctors. Conclusion: Robot-assisted tumor surgery nursing has a definite effect on patients’ rehabilitation in the operating room. 展开更多
关键词 ROBOTICS Tumor Surgery Operating Room Care REHABILITATION
下载PDF
具有可见光增强芬顿活性的Ⅱ型2D/2D Cu2ZnSnS4/Bi2WO6异质结(英文) 被引量:3
19
作者 郭莉 张开来 +5 位作者 韩宣宣 赵强 张媛媛 戚勉 王丹军 付峰 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第3期503-513,共11页
高级氧化工艺(AOPs)是一种处理有机污染物的极具吸引力的技术.大量的前期研究工作集中在通过芬顿反应(Fenton)降解有机污染物.然而,芬顿反应需要在酸性条件下进行,必须在其过程中进行预处理.同时,反应后产生的含铁污泥需要进一步处理以... 高级氧化工艺(AOPs)是一种处理有机污染物的极具吸引力的技术.大量的前期研究工作集中在通过芬顿反应(Fenton)降解有机污染物.然而,芬顿反应需要在酸性条件下进行,必须在其过程中进行预处理.同时,反应后产生的含铁污泥需要进一步处理以满足排放要求,从而限制了芬顿反应的发展.作为另一种AOPs,光催化技术因反应条件温和、操作简单和选择性好等优点受到广泛关注.研究表明,各种铁基和铜半导体光催化材料形成光-芬顿(Photo-Fenton)系统,可有效解决芬顿反应中高价金属离子/低价金属离子的循环问题.为了充分利用芬顿氧化技术和光催化氧化技术在降解有机污染物方面的各自优势,构建具有宽太阳光谱响应的新型光芬顿催化剂具有重要意义.由于其独特的层状结构和优越的有机物光催化性能,Bi2WO6作为结构最为简单的钙钛矿型层状氧化物,其禁带宽度为2.6-2.8 eV,可响应可见光,已成研究最多的光催化材料之一.研究表明,将Bi2WO6与合适的助催化剂耦合以构建异质结是提高光生载流子分离效率、拓宽Bi2WO6可见光响应范围的一种有效策略.在众多的窄带隙半导体助催化材料中,Cu2ZnSnS4作为一种p-型窄带隙半导体,可以响应可见光甚至近红外光.近年来,已经广泛报道了Cu2ZnSnS4可以作为与其他半导体光催化剂进行结合以提高光催化活性的有效助催化剂.在本文中,新型Cu2ZnSnS4/Bi2WO6(CZTS/BWO)异质结构通过简单的二次溶剂热法构建.异质结的成功形成得到了一系列表征方法的证实,比如XPS和HR-TEM.光催化活性结果表明,制备的CZTS/BWO异质结对有机污染物的降解具有优异的光催化性能,特别是当CZTS相对于异质结中BWO的质量分数为2%时.此外,加入过氧化氢(H2O2)可进一步提高染料和抗生素的降解效率.增强的光催化和光芬顿降解性能主要是由于BWO的引入,其提供了更多的活性位点,扩展了太阳光谱响应范围并加速了Cu(Ⅱ)/Cu(Ⅰ)的循环.催化剂的催化活性在经过四次循环实验后并没有显著降低.最终我们合理假设了光催化和光-芬顿催化机理.本项研究可为设计新型光-芬顿催化剂提供新的视角,即共同利用光催化活性和芬顿活性进行废水中残留有机物的净化. 展开更多
关键词 Cu2ZnSnS4 Bi2WO6 2D/2D异质结 光芬顿 光催化
下载PDF
铅修饰纳米多孔铂催化剂对甲酸氧化的电活性(英文)
20
作者 张媛媛 易清风 +3 位作者 左葛琨琨 邹涛 刘小平 周秀林 《电化学》 CAS CSCD 北大核心 2018年第3期270-278,共9页
用合适金属修饰的铂催化剂能够显著增强其对甲酸氧化的电活性.本文以水热法制备了钛负载的纳米多孔铂电极(nanoPt/Ti),然后采用循环伏安法,通过扫描不同的周数(n),用适量的铅对nanoPt/Ti电极进行修饰,得到一种新型的铅修饰的纳米多孔铂... 用合适金属修饰的铂催化剂能够显著增强其对甲酸氧化的电活性.本文以水热法制备了钛负载的纳米多孔铂电极(nanoPt/Ti),然后采用循环伏安法,通过扫描不同的周数(n),用适量的铅对nanoPt/Ti电极进行修饰,得到一种新型的铅修饰的纳米多孔铂电极(nano Pb_((n))-Pt/Ti).采用循环伏安(CV)、计时电流和计时电位法研究其对对甲酸氧化的电活性.CV结果显示nanoPt/Ti和nanoPb_((n))-Pt/Ti电极对甲酸氧化表现出较高的催化活性,并且nanoPb_((20))-Pt/Ti电极对甲酸氧化的起始电位为-0.06 V,相比nanoPt/Ti电极的起始电位(0.06 V),明显有所负移.此外,nanoPb_((20))-Pt/Ti电极的第一个氧化峰电流密度为12.7 mA·cm^(-2),远远大于nanoPt电极(4.4 mA·cm^(-2));计时电流显示在电位为0.1 V时,在0.5 mol·L^(-1)H_2SO_4+1 mol·L^(-1 )HCOOH溶液中,nanoPb_((20))-Pt/Ti电极达到稳定时的电流为8.09 mA·cm^(-2),是nanoPt电极的60倍,表明铅修饰的nanoPt/Ti对甲酸氧化的电活性急剧增加;在1.5mA、2 mA、2.2 mA和2.5 mA下的计时电位结果表明,nanoPb_((20))-Pt/Ti电极上甲酸氧化过程表现出显著的电化学振荡,且和nano Pt/Ti电极相比,振荡现象能持续更长的时间,说明nanoPb_((20))-Pt/Ti电极具有更强的表面抗毒化能力. 展开更多
关键词 甲酸氧化 纳米多孔Pt 纳米多孔Pb-Pt 电化学震荡
下载PDF
上一页 1 2 9 下一页 到第
使用帮助 返回顶部