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无机化学中“酸碱解离”教学内容的重构探讨
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作者 李淑妮 翟全国 +4 位作者 王颖 袁文玉 张鹏 胡满成 高胜利 《大学化学》 CAS 2024年第1期57-62,共6页
依据素质教育中知识-能力-素质有机融合的思想指导,对《无机化学》酸碱解离内容进行重组,构建新的课程设计模块。内容重组扩充为5个模块,包括电解质溶液基础、酸碱理论概述、酸碱强度、弱酸弱碱解离平衡和酸碱滴定与误差基本概念。教学... 依据素质教育中知识-能力-素质有机融合的思想指导,对《无机化学》酸碱解离内容进行重组,构建新的课程设计模块。内容重组扩充为5个模块,包括电解质溶液基础、酸碱理论概述、酸碱强度、弱酸弱碱解离平衡和酸碱滴定与误差基本概念。教学内容的重构在保证基本面知识结构完整的前提下与时俱进,从专业能力方面促进学生发展。 展开更多
关键词 电解质 酸碱理论 酸碱平衡 误差 课程重组
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Establishing VIGS and CRISPR/Cas9 techniques to verify RsPDS function in radish
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作者 Jiali Ying Yan Wang +10 位作者 Liang Xu Tiaojiao Qin Kai Xia peng zhang Yinbo Ma Keyun zhang Lun Wang Junhui Dong Lianxue Fan Yuelin Zhu Liwang Liu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1557-1567,共11页
Virus-induced gene silencing(VIGS)and clustered regularly interspaced short palindromic repeats/CRISPR-associated protein(CRISPR/Cas)systems are effective technologies for rapid and accurate gene function verification... Virus-induced gene silencing(VIGS)and clustered regularly interspaced short palindromic repeats/CRISPR-associated protein(CRISPR/Cas)systems are effective technologies for rapid and accurate gene function verification in modern plant biotechnology.However,the investigation of gene silencing and editing in radish remains limited.In this study,a bleaching phenotype was generated through the knockdown of RsPDS using tobacco rattle virus(TRV)-and turnip yellow mosaic virus(TYMV)-mediated gene silencing vectors.The TYMV-mediated gene silencing efficiency was higher than the TRV-based VIGS system in radish.The expression level of RsPDS was significantly inhibited using VIGS in'NAU-067'radish leaves.The rootless seedlings of‘NAU-067'were infected with Agrobacterium rhizogenes using the 2300GN-Ubi-RsPDS-Cas9 vector with two target sequences.Nine adventitious roots were blue with GUs staining,and four of these adventitious roots were edited at target sequence 1 of the RsPDS gene as indicated by Sanger sequencing.Furthermore,albino lines were generated with A.tumefaciens-mediated transformation of radish cotyledons.Five base substitutions and three base deletions occurred at target sequence 2 in Line 1,and three base insertions and three base substitutions occurred at target sequence 1 in Line 2.This study shows that VIGS and CRISPR/Cas9 techniques can be employed to precisely verify the biological functions of genes in radish,which will facilitate the genetic improvement of vital horticultural traits in radish breeding programs. 展开更多
关键词 Raphanus sativus L. VIGS CRISPR/Cas9 Agrobacterium rhizogenes A.tumefaciens RsPDS
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Strategies of selective electroreduction of aqueous nitrate to N_(2) in chloride-free system:A critical review
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作者 Fukuan Li Weizhe zhang +2 位作者 peng zhang Ao Gong Kexun Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第2期198-216,共19页
Electroreduction of nitrate has been gaining wide attention in recent years owing to it's beneficial for converting nitrate into benign N_(2) from the perspective of electrocatalytic denitrification or into value-... Electroreduction of nitrate has been gaining wide attention in recent years owing to it's beneficial for converting nitrate into benign N_(2) from the perspective of electrocatalytic denitrification or into value-added ammonia from the perspective of electrocatalytic NH_(3) synthesis.By reason of the undesired formation of ammonia is dominant during electroreduction of nitrate-containing wastewater,chloride has been widely used to improve N_(2) selectivity.Nevertheless,selective electroreduction of nitrate to N2 gas in chloride-containing system poses several drawbacks.In this review,we focus on the key strategies for efficiently enhancing N_(2) selectivity of electroreduction of nitrate in chloride-free system,including optimal selection of elements,combining an active metal catalyst with another metal,manipulating the crystalline morphology and facet orientation,constructing core–shell structure catalysts,etc.Before summarizing the strategies,four possible reaction pathways of electro-reduction of nitrate to N_(2) are discussed.Overall,this review attempts to provide practical strategies for enhancing N2 selectivity without the aid of electrochlorination and highlight directions for future research for designing appropriate electrocatalyst for final electrocatalytic denitrifi-cation. 展开更多
关键词 NITRATE CHLORIDE ELECTROREDUCTION SELECTIVITY NITROGEN
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In-situ construction of abundant active centers on hierarchically porous carbon electrode toward high-performance phosphate electrosorption: Synergistic effect of electric field and capture sites
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作者 peng zhang Fukuan Li +6 位作者 Mingming He Silu Huo Xueli zhang Benqiang Cen Dezhi Fang Kexun Li Hao Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期126-137,共12页
Phosphate removal is crucial for eutrophication control and water quality improvement.Electro-assisted adsorption,an eco-friendly elec-trosorption process,exhibited a promising potential for wastewater treatment.Howev... Phosphate removal is crucial for eutrophication control and water quality improvement.Electro-assisted adsorption,an eco-friendly elec-trosorption process,exhibited a promising potential for wastewater treatment.However,there are few works focused on phosphate electro-sorption,and reported electrodes cannot attach satisfactory removal capacities and rates.Herein,electro-assisted adsorption of phosphate via in-situ construction of La active centers on hierarchically porous carbon(LaPC)has been originally demonstrated.The resulted LaPC composite not only possessed a hierarchically porous structure with uniformly dispersed La active sites,but also provided good conductivity for interfacial electron transfer.The LaPC electrode achieved an ultrahigh phosphate electrosorption capability of 462.01 mg g^(-1) at 1 V,outperforming most existing electrodes.The superior phosphate removal performance originates from abundant active centers formed by the coupling of electricfield and capture sites.Besides,the stability and selectivity toward phosphate capture were maintained well even under comprehensive conditions.Moreover,a series of kinetics and isotherms models were employed to validate the electrosorption process.This work demonstrates a deep understanding and promotes a new level of phosphate electrosorption. 展开更多
关键词 Electro-assisted adsorption ELECTROSORPTION Phosphate removal Active centers MOF-derived carbon
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Unexpected divergence in magnetoreceptor MagR from robin and pigeon linked to two sequence variations
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作者 Shun Wang peng zhang +12 位作者 Fan Fei Tianyang Tong Xiujuan Zhou Yajie Zhou Jing zhang Mengke Wei Yanqi zhang Lei zhang Yulong Huang Lin zhang Xin zhang Tiantian Cai Can Xie 《Zoological Research》 SCIE CSCD 2024年第1期69-78,共10页
Birds exhibit extraordinary mobility and remarkable navigational skills,obtaining guidance cues from the Earth’s magnetic field for orientation and long-distance movement.Bird species also show tremendous diversity i... Birds exhibit extraordinary mobility and remarkable navigational skills,obtaining guidance cues from the Earth’s magnetic field for orientation and long-distance movement.Bird species also show tremendous diversity in navigation strategies,with considerable differences even within the same taxa and among individuals from the same population.The highly conserved iron and iron-sulfur cluster binding magnetoreceptor(MagR)protein is suggested to enable animals,including birds,to detect the geomagnetic field and navigate accordingly.Notably,MagR is also implicated in other functions,such as electron transfer and biogenesis of iron-sulfur clusters,raising the question of whether variability exists in its biochemical and biophysical features among species,particularly birds.In the current study,we conducted a comparative analysis of MagR from two different bird species,including the migratory European robin(Erithacus rubecula)and the homing pigeon(Columba livia).Sequence alignment revealed an extremely high degree of similarity between the MagRs of these species,with only three sequence variations.Nevertheless,two of these variations underpinned significant differences in metal binding capacity,oligomeric state,and magnetic properties.These findings offer compelling evidence for the marked differences in MagR between the two avian species,potentially explaining how a highly conserved protein can mediate such diverse functions. 展开更多
关键词 Homing and migration Animal navigation Magnetoreceptor(MagR) Diverse navigation pattern Conserved protein
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Can soil organic carbon sequestration and the carbon management index be improved by changing the film mulching methods in the semiarid region?
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作者 Jialin Yang Liangqi Ren +6 位作者 Nanhai zhang Enke Liu Shikun Sun Xiaolong Ren Zhikuan Jia Ting Wei peng zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1541-1556,共16页
Plastic film mulching has been widely used to increase maize yield in the semiarid area of China.However, whether long-term plastic film mulching is conducive to agricultural sustainability in this region remains cont... Plastic film mulching has been widely used to increase maize yield in the semiarid area of China.However, whether long-term plastic film mulching is conducive to agricultural sustainability in this region remains controversial.A field experiment was initiated in 2013 with five different film mulching methods:(i) control method, flat planting without mulching (CK),(ii) flat planting with half film mulching (P),(iii) film mulching on ridges and planting in narrow furrows(S),(iv) full film mulching on double ridges (D), and (v) film mulching on ridges and planting in wide furrows (R).The effects on soil organic carbon (SOC) content, storage, and fractions, and on the carbon management index (CMI)were evaluated after nine consecutive years of plastic film mulching.The results showed that long-term plastic film mulching generally maintained the initial SOC level.Compared with no mulching, plastic film mulching increased the average crop yield, biomass yield, and root biomass by 48.38, 35.06, and 37.32%, respectively, which led to the improvement of SOC sequestration.Specifically, plastic film mulching significantly improved CMI, and increased the SOC content by 13.59%, SOC storage by 7.47%and easily oxidizable organic carbon (EOC) by 13.78%on average,but it reduced the other labile fractions.SOC sequestration and CMI were improved by refining the plastic film mulching methods.The S treatment had the best effect among the four mulching methods, so it can be used as a reasonable film mulching method for sustainable agricultural development in the semiarid area. 展开更多
关键词 plastic film mulching soil organic carbon labile organic carbon fractions semiarid area
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Electronic origin of structural degradation in Li-rich transition metal oxides:The case of Li_(2)MnO_(3)and Li_(2)RuO_(3)
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作者 peng zhang 《Journal of Semiconductors》 EI CAS CSCD 2024年第4期82-86,共5页
Li_(2)MnO_(3)and Li_(2)RuO_(3)represent two prototype Li-rich transition metal(TM)oxides as high-capacity cathodes for Li-ion batteries,which have similar crystal structures but show quite different cycling performanc... Li_(2)MnO_(3)and Li_(2)RuO_(3)represent two prototype Li-rich transition metal(TM)oxides as high-capacity cathodes for Li-ion batteries,which have similar crystal structures but show quite different cycling performances.Here,based on the first-princi-ples calculations,we systematically studied the electronic structures and defect properties of these two Li-rich cathodes,in order to get more understanding on the structural degradation mechanism in Li-rich TM oxides.Our calculations indicated that the structural and cycling stability of Li_(2)MnO_(3)and Li_(2)RuO_(3)depend closely on their electronic structures,especially the energy of their highest occupied electronic states(HOS),as it largely determines the defect properties of these cathodes.For Li_(2)MnO_(3)with low-energy HOS,we found that,due to the defect charge transfer mechanism,various defects can form spontaneously in its host structure as Li ions are extracted upon delithiation,which seriously deteriorates its structural and cycling stability.While for Li_(2)RuO_(3),on the other hand,we identified that the high-energy HOS prevents it from the defect formation upon delithi-ation and thus preserve its cycling reversibility.Our studies thus illustrated an electronic origin of the structural degradation in Li-rich TM oxides and implied that it is possible to improve their cycling performances by carefully adjusting their TM compo-nents. 展开更多
关键词 defects Li-ion batteries first-principles calculations
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Three novel rare TP53 fusion mutations in a patient with multiple primary cancers:a case report
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作者 Mengyao Lu Xuemei zhang +2 位作者 Qian Chu Yuan Chen peng zhang 《Oncology and Translational Medicine》 2024年第1期47-51,共5页
As survival rates improve and detection technologies advance,the occurrence of multiple primary cancers(MPCs)has been increasing.Approximately 16%of cancer survivors develop a subsequent malignancy,with lung cancer of... As survival rates improve and detection technologies advance,the occurrence of multiple primary cancers(MPCs)has been increasing.Approximately 16%of cancer survivors develop a subsequent malignancy,with lung cancer often developing after esophageal cancer due to potential“field cancerization”effects.Despite this observation,the genetic heterogeneity underlying MPCs remains understudied.However,the recent emergence of genetic testing has expanded the scope of investigations into MPCs to investigate signatures underlying cancer predisposition.This report reveals 3 unprecedented TP53 fusion mutations in a Chinese patient afflicted by MPCs,namely,AP1M2–TP53(A1;T11)fusion,TP53–ILF3(T10;I13)fusion,and SLC44A2–TP53(S5;T11)fusion.This patient exhibited an extended period of survival after diagnosis of extensive-stage small cell lung cancer,which occurred 6 years after the diagnosis of esophageal squamous cell cancer.This unique reportmay provide supplementary data that enhance our understanding of the genetic landscape ofMPCs. 展开更多
关键词 Multiple primary cancers TP53 fusion mutation Esophageal squamous cell cancer Extensive-stage small cell lung cancer IMMUNOTHERAPY Antiangiogenic therapy
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复杂地形风电场微观选址优化算法研究
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作者 王晓理 杨凤志 +1 位作者 张棚 范志强 《风机技术》 2024年第1期77-82,87,共7页
我国拥有丰富、分布广泛的风能资源,其中复杂地形的风能开发正成为新的焦点。在风能开发中微观选址极为重要。由于传统风电场微观选址优化在复杂地形中效率低下,难以充分利用风资源,本文提出两种更高效的优化方法。其一,采用灰狼优化算... 我国拥有丰富、分布广泛的风能资源,其中复杂地形的风能开发正成为新的焦点。在风能开发中微观选址极为重要。由于传统风电场微观选址优化在复杂地形中效率低下,难以充分利用风资源,本文提出两种更高效的优化方法。其一,采用灰狼优化算法对风电场选址进行优化,优化主要以单个风力机容量系数为个体,总发电量的提高为目标,多优化个体共同构成电场整体排布方案。这种针对复杂地形下风电场微观选址优化的方式,能显著提升优化效率,有效实现选址优化目的。其二,采用作图法,分析风电场内特定高度的容量系数和风向分布,提出多种排布方案,基于发电量最大化原则选定方案实现优化,这种方法直接锁定最优结果,减少计算资源消耗。 展开更多
关键词 复杂地形 微观选址 灰狼优化算法 有限寻优 容量系数
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Muscle satellite cells:one of the important factors in the occurrence and development of sarcopenia
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作者 peng zhang Wen-Hui Jiang +2 位作者 Juan-Juan Gao Wen-Xia Yu Shu-Quan Lv 《Life Research》 2024年第2期28-31,共4页
Sarcopenia,or muscle loss,has been one of the hot topics in the medical field in recent years.Due to limited attention and effective treatments for sarcopenia in the past,many patients,especially the elderly,suffered ... Sarcopenia,or muscle loss,has been one of the hot topics in the medical field in recent years.Due to limited attention and effective treatments for sarcopenia in the past,many patients,especially the elderly,suffered irreversible damage to their motor function caused by sarcopenia.However,recent scientific studies have found that the occurrence and development of sarcopenia are closely related to the function and quantity of muscle satellite cells.This article briefly discusses the relationship between muscle satellite cells and sarcopenia. 展开更多
关键词 SARCOPENIA muscle satellite cells skeletal muscle cells
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Study on the Efficacy of Shugan Jieyu Capsules Combined with Trazodone in Patients with Post-Stroke Depression and Insomnia
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作者 Tie Mao Yong Yang +6 位作者 Xi Chen Ping Liu peng zhang Chunju Wu Xiaojun Hou Cuicui Rong Jujun Xue 《Journal of Clinical and Nursing Research》 2024年第2期50-55,共6页
Objective:To analyze the effectiveness of applying ShuGan JieYu Capsules(SGJYC)combined with trazodone in patients with post-stroke depression(PSD)with insomnia.Methods:60 cases of PSD with insomnia patients admitted ... Objective:To analyze the effectiveness of applying ShuGan JieYu Capsules(SGJYC)combined with trazodone in patients with post-stroke depression(PSD)with insomnia.Methods:60 cases of PSD with insomnia patients admitted to the hospital from May 2022 to May 2023 were selected and randomly divided into a reference group(trazodone)and a research group(SGJYC combined with trazodone)of 30 cases each.Statistics were analyzed using the Hamilton Depression Rating Scale(HAM-D),Pittsburgh Sleep Quality Index(PSQI),and Activities of Daily Living(ADL)scale before treatment and 4,8,and 12 weeks after treatment.Results:Before treatment,The results of HAM-D,PSQI,and ADL scale studies in the two groups before treatment were not statistically significant(P>0.05);4,8,and 12 weeks after treatment,the results of HAM-D and PSQI studies in the research group were lower than that of the reference group,and the results of ADL scale studies were higher than that of the reference group.There was a significant difference between the groups(P<0.05).The total adverse reaction rate of the research group was lower than that of the reference group,and there was a significant difference between the groups(P<0.05).Conclusion:The combination of SGJYC and trazodone reduced depression in post-stroke patients,corrected insomnia,improved sleep quality,was safe,and had a low rate of adverse reactions. 展开更多
关键词 ShuGan JieYu Capsules Trazodone STROKE DEPRESSION INSOMNIA
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Safety Length Simulation of Natural Gas Pipeline Subjected to Transverse Landslide
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作者 Guizhi Li peng zhang +2 位作者 Zhixiang Li Zunhai Ke Gengxin Wu 《World Journal of Engineering and Technology》 2023年第1期67-80,共14页
The safety of natural gas pipeline is often severely threatened by the transverse landslide. At home and abroad, it is the first time to study the safe length of the pipeline when affected by landslide, and take ... The safety of natural gas pipeline is often severely threatened by the transverse landslide. At home and abroad, it is the first time to study the safe length of the pipeline when affected by landslide, and take the safe length of the pipeline as an engineering practical index. Therefore, it is of great significance to study the influence of transverse landslide affecting the safety of natural gas pipeline when a certain length of pipeline is thrusted, and to establish practical index and simulation method for prediction and prevention of the landslide hazards to gas pipeline. Based on the current research results, this study could be divided into three steps: First of all, with the help of ANSYS finite element software, the model of transverse landslide acting on the gas pipeline can be set up, then the length value of gas pipeline safely withstanding transverse landslide can be calculated;Secondly, using the strength reduction method, which is commonly used in the research of landslide stability, can establish three-dimensional model of the landslide and pipes in the ABAQUS finite element software, next, under the same landslide pushed length, the calculation results will be obtained;Finally, to draw reliable conclusions, all calculated results of the former two methods will be linked to synthetically and comparatively analyze, then the length value of common X80 gas pipeline safely bearing transverse landslide can be got. All results can provide some references for engineering and design. 展开更多
关键词 Transverse Landslide Gas Pipeline Finite Elements Simulation Strength Reduction Method
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太阳能驱动H_(2)O_(2)的原位生产与利用:自循环光催化芬顿系统
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作者 张鹏 李佑稷 李鑫 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第1期4-6,共3页
人工光合成通过模拟自然界的光合作用合成人类必须的化学品,并在光解水制氢、水和氧气反应制备双氧水等领域得到了广泛的关注.然而,双氧水不稳定导致产物的分离和提纯成本高,阻碍了其进一步发展.为解决上述问题,最近,南京理工大学张侃... 人工光合成通过模拟自然界的光合作用合成人类必须的化学品,并在光解水制氢、水和氧气反应制备双氧水等领域得到了广泛的关注.然而,双氧水不稳定导致产物的分离和提纯成本高,阻碍了其进一步发展.为解决上述问题,最近,南京理工大学张侃教授团队联合韩国延世大学Jong Hyeok Park教授,河海大学敖燕辉教授开发出了基于人工树叶的自循环光芬顿系统,在碳酸氢盐溶液和微量Mn^(2+)/Mn^(4+)的协同作用下,成功地将原位生产的双氧水进一步生成活性含氧物种(ROSs)并用于污水处理,实现了高效太阳能驱动H_(2)O_(2)的原位生产与利用(见Nat.Commun.,2022,13,4982).该工作首先利用人工树叶阴极部分对Mn^(4+)离子还原,实现了Mn^(2+)/Mn^(4+)氧化还原物种在催化体系中的循环使用,确保了芬顿体系的可持续性.其次,通过对耦合的光阳极以及阴极的表面动力学过程进行优化,构建了太阳能到双氧水转换效率超过1.46%的人工树叶.实验发现,70 cm^(2)的大面积器件可在70 min内矿化含有5 ppm罗丹明B,5 ppm亚甲基蓝和5 ppm对硝基苯酚的混合污水,并表现出超过一个月的稳定性.综上,本文可为发展新的太阳能驱动环境处理模式提供借鉴. 展开更多
关键词 光电催化 双氧水合成 芬顿反应 人工树叶 环境处理
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失效铝合金平底无铆连接接头的原位固相修复方法
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作者 张鹏 陈超 +5 位作者 赵升吨 费亮瑜 曹杨峰 张硕文 韩晓兰 李坤 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第5期1361-1372,共12页
为了修复失效平底无铆连接接头并提高其力学性能,提出一种原位固相修复方法。通过对比研究平底无铆连接接头和修复接头的显微组织、力学性能和断裂失效行为,验证修复方法的可行性和有效性。结果表明,失效平底无铆连接接头的断裂颈部被... 为了修复失效平底无铆连接接头并提高其力学性能,提出一种原位固相修复方法。通过对比研究平底无铆连接接头和修复接头的显微组织、力学性能和断裂失效行为,验证修复方法的可行性和有效性。结果表明,失效平底无铆连接接头的断裂颈部被成功地原位修复。焊核的显微组织被充分细化,使得修复接头的力学性能得到提升。转速和持续加热时间对修复接头的力学性能起着至关重要的作用。与平底无铆连接接头相比,冶金结合使修复接头的力学性能得到加强。修复接头的最大拉剪强度提高了409.90%,最大断裂伸长量提高了68.92%。断裂失效行为表明,修复接头的强度明显高于原始平底无铆连接接头,这说明失效平底无铆连接接头的修复方法是可行有效的。 展开更多
关键词 平底无铆连接 固相修复 平均晶粒尺寸 拉剪强度 断裂失效行为
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不同脂质层厚度干眼患者泪膜稳定性的观察研究 被引量:2
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作者 张鹏 韩坤岭 +1 位作者 王延铮 王延岭 《国际眼科杂志》 CAS 北大核心 2023年第5期864-866,共3页
目的:探讨不同脂质层厚度条件下泪膜稳定性的差异。方法:纳入2020-06/2021-12于我院就诊的干眼患者194例384眼,应用角膜地形图仪行双眼泪河高度、首次泪膜破裂时间和脂质层厚度测量,分析不同脂质层厚度条件下双眼泪河高度、首次泪膜破... 目的:探讨不同脂质层厚度条件下泪膜稳定性的差异。方法:纳入2020-06/2021-12于我院就诊的干眼患者194例384眼,应用角膜地形图仪行双眼泪河高度、首次泪膜破裂时间和脂质层厚度测量,分析不同脂质层厚度条件下双眼泪河高度、首次泪膜破裂时间的差异及其相关性。结果:根据脂质层厚度将纳入患者(384眼)分为脂质丰富组(49眼)、脂质平衡组(27眼)、脂质轻微缺乏组(266眼)、脂质显著缺乏组(42眼),四组泪河高度有差异(P=0.022),首次泪膜破裂时间无差异(P=0.322)。脂质层厚度分级与泪河高度呈正相关(r_(s)=0.143,P=0.006),与首次泪膜破裂时间无相关性(r_(s)=-0.090,P=0.083);泪河高度与首次泪膜破裂时间也无相关性(r_(s)=0.038,P=0.460)。结论:泪膜脂质层厚度不同的干眼患者泪膜稳定性无明显差异。 展开更多
关键词 泪膜 脂质层 干眼 泪河高度 泪膜破裂时间
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构建Cu台阶位促进电催化CO_(2)还原制醇类化学品的研究
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作者 高晖 张恭 +8 位作者 程东方 王永涛 赵静 李晓芝 杜晓伟 赵志坚 王拓 张鹏 巩金龙 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第9期187-195,共9页
电催化CO_(2)制备高附加值的化学品是解决当前碳排放问题的可行技术路线之一.其中,合成醇类化合物因具有广泛用途和高价值而备受关注.在电催化CO_(2)还原合成多碳醇反应中,关键中间体*CH_(2)CHO容易发生热力学有利的脱氧反应而生成C2H4... 电催化CO_(2)制备高附加值的化学品是解决当前碳排放问题的可行技术路线之一.其中,合成醇类化合物因具有广泛用途和高价值而备受关注.在电催化CO_(2)还原合成多碳醇反应中,关键中间体*CH_(2)CHO容易发生热力学有利的脱氧反应而生成C2H4,降低了醇类产物的选择性.由于电催化CO_(2)还原是一个表面结构敏感的反应,因此可以通过设计Cu基催化剂的特定表面结构,实现对反应路径的有效调节,从而提升醇类产物的选择性.本课题组前期通过密度泛函理论(DFT)计算和主成分分析法等对Cu基催化剂的构效关系进行解析,说明配位不饱和的台阶位点有望高效地促进醇类产物的生成.本文进一步从实验角度,证明了配位不饱和的台阶位点是生成醇类产物的活性位点.本文采用CO分子作为还原剂制备了CuO衍生的金属Cu催化剂(COD-Cu),利用CO分子对Cu表面的重构作用,获得了具有丰富台阶位点的Cu催化剂.而通过H_(2)还原制备的金属Cu催化剂(HOD-Cu)对照样表面则多为平面位点.X射线衍射和原位拉曼光谱结果表明,CuO前驱体经过CO或H_(2)还原后被完全还原为金属态,并且在电化学还原条件下依旧呈现金属态,排除了催化剂价态对反应的影响.扫描电镜结果表明,两种催化剂的形貌没有明显区别,排除了催化剂形貌对反应的影响.高分辨透射电镜结果表明,COD-Cu表面因为CO的重构作用,产生相较于HOD-Cu更多的台阶位点,这与CO原位红外光谱结果一致(COD-Cu催化剂在2080 cm~(–1)波数处具有明显的台阶位点CO吸附峰).电化学CO_(2)还原活性测试结果表明,COD-Cu表现出更高的醇类产物选择性,相较于HOD-Cu,法拉第效率与部分电流密度均提升了5倍以上,醇类产物的法拉第效率达到40.5%,部分电流密度达到56.3 mAcm~(-2),产物中醇/烯烃比值为2.2.这表明台阶位点对调控反应路径促进醇类生成具有重要作用.结合原位衰减全反射表面增强傅里叶变换红外吸收光谱的阶跃电位和Ar气吹扫实验结果表明,COD-Cu因具有更多的台阶位点而表现出更高的催化CO_(2)到*CO反应活性,并有效促进后续的C–C偶联反应.通过热退火实验制备了具有不同台阶位点含量的COD-Cu催化剂,其台阶位点的含量与醇类产物的选择性保持良好的线性关系,进一步验证了台阶位点是促进醇类产物生成活性位点的结论.DFT结果也表明,台阶位点可以有效的提升关键中间体*CH_(2)CHO中C–O键强度,从而抑制C–O键断裂,促进醇类产物的生成.综上,本文提出了一种通过催化剂活性位点设计调控电催化CO_(2)还原反应路径的有效策略,为解析催化剂构效关系、明确活性位点提供参考.得益于催化科学的快速发展,具有高活性的CO_(2)还原电催化剂不断涌现,未来可在发展活性位点精细化调控方法、开发新型原位瞬态表征技术、创新催化剂失活机制原位研究方法等方面做出更多的努力. 展开更多
关键词 电催化 CO_(2)还原 台阶位点
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胃肠安丸通过抑制上皮间质化抑制TNBS诱导的大鼠溃疡性结肠炎
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作者 齐雅馨 王梦 +10 位作者 柴丽娟 张敏 贾思童 纳塔鹏威蔡 王琳 王玉晶 宋霁翔 张晗 王怡 张鹏 苗琳 《Acupuncture and Herbal Medicine》 2023年第2期107-115,共9页
[目的]探讨胃肠安丸对大鼠溃疡性结肠炎(UC)的抑制作用及其作用机制。[方法]建立2,4,6-三硝基苯磺酸(TNBS)诱导的大鼠UC模型,灌胃给予胃肠安(WCA)1周;记录大鼠体重和结肠长度,进行疾病活动指数(DAI)评分和结肠黏膜损伤指数(CMDI)评分;... [目的]探讨胃肠安丸对大鼠溃疡性结肠炎(UC)的抑制作用及其作用机制。[方法]建立2,4,6-三硝基苯磺酸(TNBS)诱导的大鼠UC模型,灌胃给予胃肠安(WCA)1周;记录大鼠体重和结肠长度,进行疾病活动指数(DAI)评分和结肠黏膜损伤指数(CMDI)评分;用免疫组织化学法检测结肠病理变化。细胞水平上,考察WCA对脂多糖(LPS)刺激的THP-1细胞炎症因子表达的影响。通过免疫荧光法分别考察WCA对UC大鼠结肠组织和LPS刺激的THP-1细胞条件培养基(CM)处理的结肠上皮Caco-2细胞的上皮-间质化(EMT)标志物E-钙粘蛋白和波形蛋白的表达。[结果]WCA可以显著抑制UC大鼠体重的减轻和结肠长度的缩短,降低疾病相关的DAI和CMDI评分,改善结肠病理损伤;UC结肠组织髓过氧化物酶(MPO)活性和细胞因子表达的上升已被明显抑制。在THP-1细胞中,WCA及其活性成分可以显著抑制LPS诱导的干扰素诱导蛋白10(IP-10)、肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-6和NF-κB抑制剂(IkBα)mRNA水平的表达。在UC大鼠和CM刺激的Caco-2细胞中E-钙粘蛋白表达下调,波形蛋白表达上调,给予WCA治疗处理后,上述EMT现象被明显抑制。[结论]本研究表明,WCA可以通过抑制炎症诱导的结肠EMT减轻大鼠UC的发展。 展开更多
关键词 上皮间质化 炎症 中药 溃疡性结肠炎 胃肠安
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The Critical Role of Fillers in Composite Polymer Electrolytes for Lithium Battery 被引量:2
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作者 Xueying Yang Jiaxiang Liu +5 位作者 Nanbiao Pei Zhiqiang Chen Ruiyang Li Lijun Fu peng zhang Jinbao Zhao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第5期339-375,共37页
With excellent energy densities and highly safe performance,solidstate lithium batteries(SSLBs)have been hailed as promising energy storage devices.Solid-state electrolyte is the core component of SSLBs and plays an e... With excellent energy densities and highly safe performance,solidstate lithium batteries(SSLBs)have been hailed as promising energy storage devices.Solid-state electrolyte is the core component of SSLBs and plays an essential role in the safety and electrochemical performance of the cells.Composite polymer electrolytes(CPEs)are considered as one of the most promising candidates among all solid-state electrolytes due to their excellent comprehensive performance.In this review,we briefly introduce the components of CPEs,such as the polymer matrix and the species of fillers,as well as the integration of fillers in the polymers.In particular,we focus on the two major obstacles that affect the development of CPEs:the low ionic conductivity of the electrolyte and high interfacial impedance.We provide insight into the factors influencing ionic conductivity,in terms of macroscopic and microscopic aspects,including the aggregated structure of the polymer,ion migration rate and carrier concentration.In addition,we also discuss the electrode-electrolyte interface and summarize methods for improving this interface.It is expected that this review will provide feasible solutions for modifying CPEs through further understanding of the ion conduction mechanism in CPEs and for improving the compatibility of the electrode-electrolyte interface. 展开更多
关键词 Composite polymer electrolytes FILLERS Ionic conductivity Electrode-electrolyte interface
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Li intercalation in an MoSe_(2) electrocatalyst:In situ observation and modulation of its precisely controllable phase engineering for a high-performance flexible Li-S battery 被引量:2
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作者 Yunke Wang Yige Zhao +5 位作者 Kangli Liu Shaobin Wang Neng Li Guosheng Shao Feng Wang peng zhang 《Carbon Energy》 SCIE CSCD 2023年第2期201-215,共15页
Sophisticated efficient electrocatalysts are essential to rectifying the shuttle effect and realizing the high performance of flexible lithium-sulfur batteries(LSBs).Phase transformation of MoSe_(2) from the 2H phase ... Sophisticated efficient electrocatalysts are essential to rectifying the shuttle effect and realizing the high performance of flexible lithium-sulfur batteries(LSBs).Phase transformation of MoSe_(2) from the 2H phase to the 1T phase has been proven to be a significant method to improve the catalytic activity.However,precisely controllable phase engineering of MoSe_(2) has rarely been reported.Herein,by in situ Li ions intercalation in MoSe_(2),a precisely controllable phase evolution from 2H-MoSe_(2) to 1T-MoSe_(2) was realized.More importantly,the definite functional relationship between cut-off voltage and phase structure was first identified for phase engineering through in situ observation and modulation methods.The sulfur host(CNFs/1T-MoSe_(2))presents high charge density,strong polysulfides adsorption,and catalytic kinetics.Moreover,Li-S cells based on it display capacity retention of 875.3mAh g^(-1) after 500 cycles at 1 C and an areal capacity of 8.71mAh cm^(-2) even at a high sulfur loading of 8.47mg cm^(-2).Furthermore,the flexible pouch cell exhibiting decent performance will endow a promising potential in the wearable energy storage field.This study proposes an effective strategy to precisely control the phase structure of MoSe_(2),which may provide the reference to fabricate the highly efficient electrocatalysts for LSBs and other energy systems. 展开更多
关键词 ELECTROCATALYSTS ELECTROSPINNING Li intercalation lithium-sulfur batteries phase engineering
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Leaf nitrogen resorption is more important than litter nitrogen mineralization in mediating the diversity–productivity relationship along a nitrogen-limited temperate forest succession chronosequence 被引量:1
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作者 peng zhang Xiao-Tao Lü +2 位作者 Guangze Jin Zhili Liu Mai-He Li 《Forest Ecosystems》 SCIE CSCD 2023年第1期132-140,共9页
The resorption of nutrients by plants before litter fall and the mineralization of nutrients from plant litter by soil processes are both important pathways supporting primary productivity. While the positive relation... The resorption of nutrients by plants before litter fall and the mineralization of nutrients from plant litter by soil processes are both important pathways supporting primary productivity. While the positive relationship between plant biodiversity and primary productivity is widely accepted for natural ecosystems, the roles of nutrient resorption and mineralization in mediating that relationship remains largely unknown. Here, we quantified the relative importance of nitrogen(N) resorption and N mineralization in driving plant community N investment and the correlation between species diversity and community productivity along an N-limited successional chronosequence of the mixed broadleaved–Korean pine(Pinus koraiensis) forest in northeastern China. Leaf N resorption efficiency(NRE) at the community level increased significantly along the successional chronosequence,whereas litter N mineralization rate decreased significantly. Leaf NRE was more important than litter N mineralization rate in driving the diversity–productivity relationship. However, higher leaf NRE led to less N mineralization as succession progressed along the chronosequence. Our results highlight the importance of the N resorption pathway rather than the N mineralization pathway for forest N acquisition with community succession,and they provide mechanistic insights into the positive effects of biodiversity on ecosystem functioning. In future forest management practices, we recommend appropriate application of N fertilizer to mitigate the adverse effects of N-poor soil on seedling regeneration during late succession and thus maintain the sustainable development of temperate forest ecosystems. 展开更多
关键词 Community composition DIVERSITY Ecosystem functioning N cycling N limited Niche complementarity Trade-off
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