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Dietary polyphenols reduced the allergenicity ofβ-lactoglobulin via non-covalent interactions:a study on the structure-allergenicity relationship
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作者 Chi Zhang Qiaozhi Zhang +6 位作者 Huatao Li Zhouzhou Cheng Shiyu Fan Hujun Xie Zhongshan Gao Yan Zhang Linglin Fu 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2617-2628,共12页
Studies showed that complexation of polyphenols with milk allergens reduced their immunogenic potential.However,the relationship between structures of polyphenols and their hypoallergenic effects on milk allergens in ... Studies showed that complexation of polyphenols with milk allergens reduced their immunogenic potential.However,the relationship between structures of polyphenols and their hypoallergenic effects on milk allergens in association with physiological and conformational changes of the complexes remain unclear.In this study,polyphenols from eight botanical sources were extracted to prepare non-covalent complexes withβ-lactoglobulin(β-LG),a major allergen in milk.The dominant phenolic compounds bound toβ-LG with a diminished allergenicity were identified to investigate their respective role on the structural and allergenic properties ofβ-LG.Extracts from Vaccinium fruits and black soybeans were found to have great inhibitory effects on the IgE-and IgG-binding abilities ofβ-LG.Among the fourteen structure-related phenolic compounds,flavonoids and tannins with larger MWs and multi-hydroxyl substituents,notably rutin,EGCG,and ellagitannins were more potent to elicit changes on the conformational structures ofβ-LG to decrease the allergenicity of complexedβ-LG.Correlation analysis further demonstrated that a destabilized secondary structure and protein depolymerization caused by polyphenol-binding were closely related to the allergenicity property of formed complexes.This study provides insights into the understanding of structure-allergenicity relationship ofβ-LG-polyphenol interactions and would benefit the development of polyphenol-fortified matrices with hypoallergenic potential. 展开更多
关键词 Cow’s milk allergy Β-LACTOGLOBULIN Protein-polyphenol interaction ALLERGENICITY Conformational structure
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Emerging structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease
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作者 Yinglong Miao Michael S.Wolfe 《Neural Regeneration Research》 SCIE CAS 2025年第1期174-180,共7页
γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the ... γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface receptors.Mutations inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-Secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as well.However,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-secretase.In this review,we focus on recent studies of structural dynamic mechanisms ofγ-secretase.Different mechanisms,including the“Fit-Stay-Trim,”“Sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics simulations.While an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental findings.The approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-secretase.In addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is discussed.Finally,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations of theγ-secretase-substrate complexes.Comprehensive understanding of the functional mechanisms ofγ-secretase will greatly facilitate the rational design of effective drug molecules for treating familial Alzheimer’s disease and perhaps Alzheimer’s disease in general. 展开更多
关键词 Alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics NOTCH
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The Tension Cosmology, Largest Cosmic Structures and Explosions of Supernovae from SST
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作者 Sylwester Kornowski 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1029-1044,共16页
Here, using the Scale-Symmetric Theory (SST) we explain the cosmological tension and the origin of the largest cosmic structures. We show that a change in value of strong coupling constant for cold baryonic matter lea... Here, using the Scale-Symmetric Theory (SST) we explain the cosmological tension and the origin of the largest cosmic structures. We show that a change in value of strong coupling constant for cold baryonic matter leads to the disagreement in the galaxy clustering amplitude, quantified by the parameter S8. Within the same model we described the Hubble tension. We described also the mechanism that transforms the gravitational collapse into an explosion—it concerns the dynamics of virtual fields that lead to dark energy. Our calculations concern the Type Ia supernovae and the core-collapse supernovae. We calculated the quantized masses of the progenitors of supernovae, emitted total energy during explosion, and we calculated how much of the released energy was transferred to neutrinos. Value of the speed of sound in the strongly interacting matter measured at the LHC confirms that presented here model is correct. Our calculations show that the Universe is cyclic. 展开更多
关键词 scale-symmetric Theory Tension Cosmology Coupling Constants Parameters σ8 and s8 Largest Cosmic structures Dark Energy supernova Explosion Cyclic Universe
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Study of the Ballistic Impact Behavior of Protective Multi-Layer Composite Armor
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作者 Dongsheng Jia Yingjie Xu +2 位作者 Liangdi Wang Jihong Zhu Weihong Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期171-199,共29页
The abalone shell,a composite material whose cross-section is composed of inorganic and organic layers,has high strength and toughness.Inspired by the abalone shell,several multi-layer composite plates with different ... The abalone shell,a composite material whose cross-section is composed of inorganic and organic layers,has high strength and toughness.Inspired by the abalone shell,several multi-layer composite plates with different layer sequences and thicknesses are studied as bullet-proof material in this paper.To investigate the ballistic performance of this multi-layer structure,the complete characterization model and related material parameters of large deformation,failure and fracture ofAl_(2)O_(3)ceramics andCarbon Fiber Reinforced Polymer(CFRP)are studied.Then,3D finite element models of the proposed composite plates with different layer sequences and thicknesses impacted by a 12.7 mm armor-piercing incendiary(API)are built using Abaqus to predict failure.The simulation results show that the CFRP/Al2O3 ceramic/Ultrahigh Molecular Weight Polyethylene(UHMWPE)/CFRP(1 mm/4 mm/4 mm/1 mm)composite is the optimized stack of layers.The simulation results under specified layer sequence and thickness have a reasonable correlation with the experimental results and reflect the failure and fracture of the multi-layer composite protective armor. 展开更多
关键词 Protective armor COMPOsITE bionic design structure design mechanical property
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Temporal change of plankton size structure preserved by Lugol's solution:a FlowCAM study
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作者 Zijia LIU Yuan DONG +3 位作者 Qian P.LI Zhengchao WU Zaiming GE Mengzhen MA 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第1期290-299,共10页
Plankton size structure is crucial for understanding marine ecosystem dynamics and the associated biogeochemical processes.A fixation step by acid Lugol’s solution has been commonly employed to preserve plankton samp... Plankton size structure is crucial for understanding marine ecosystem dynamics and the associated biogeochemical processes.A fixation step by acid Lugol’s solution has been commonly employed to preserve plankton samples in the field.However,the acid Lugol’s solution can bias the estimation of size structure and the preserved plankton size structure can vary with time.Here,we explore the impact of sample storage time on the size-structure of the plankton community preserved by Lugol’s solution.Two short-term experiments and one long-term experiment were conducted to explore the change of plankton community size structure with the storage time:covering from a week to a month,and to nearly seven months based on particle-size data obtained by continuous Flow Cytometer and Microscope(FlowCAM)measurements.We found a linear change of plankton size with the storage time in short-term periods(less than 3 months)with a decrease of the slope but an increase of the intercept for the normalized biomass size spectrum(NBS S).However,there were opposite trends for NBSS with increasing slope but decreasing intercept after3 months.The potential causes of the distinct patterns of the NBSS parameters are addressed in terms of the interplay between particle aggregation and fragmentation.We found large changes in plankton biovolume and abundance among different size classes,which may indicate a distinct effect of acid Lugol’s solution on various plankton size classes.The mechanism driving temporal change in the size-structure of the Lugolfixed plankton community was further discussed in terms of particle aggregation and fragmentation.Finally,we emphasize that the effect of storage time should be taken into account when interpreting or comparing data of plankton community acquired from samples with various storage durations. 展开更多
关键词 Lugol’s PLANKTON size structure Flow Cytometer and Microscope(FlowCAM)
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Investigations on Structured Polyamide for Laser Sintered Body Armor
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作者 Jinhui Jiang Xinming Qian +1 位作者 Mengqi Yuan Tingchao Ji 《Journal of Beijing Institute of Technology》 EI CAS 2017年第1期38-44,共7页
Stab resistance body armor(SRBA)is essential in protecting people from knife injuries.The protective parts of traditional SRBA are made of multi-layered ultra-high molecular weight polyethylene(UHMWPE),which cause... Stab resistance body armor(SRBA)is essential in protecting people from knife injuries.The protective parts of traditional SRBA are made of multi-layered ultra-high molecular weight polyethylene(UHMWPE),which causes heavy heat stress for people wearing it.The protective parts of SRBA manufactured using laser sintering(LS)3D printing technology provide high manufacturing flexibility and low weight.Two different structures,plain plate and pyramid-structured plate,were investigated.The pyramid structure showed much higher stab resistance property then the plain plate,because of the angle and thickness effects.This is the first effort applying the LS technology and polyamide(PA)material(PA3200)on SRBA.By applying the pyramid structure on the protective layer of the SRBA,the total weight could reduce 30%-40%. 展开更多
关键词 stab resistance body armor 3D printing laser sintering pyramid structure
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Allozyme Diversity and Population Genetic Structure of Three Medicinal Epimedium Species from Hubei 被引量:4
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作者 徐艳琴 李作洲 +1 位作者 王瑛 黄宏文 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第1期56-71,共16页
Three Epimedium species, E. pubescens Maxim., E. sagittatum (Sieb. & Zucc.) Maxim., and E. wushanense T. S. Ying, which are sympatrically distributed in the western Hubei Province, have been used in traditional Chi... Three Epimedium species, E. pubescens Maxim., E. sagittatum (Sieb. & Zucc.) Maxim., and E. wushanense T. S. Ying, which are sympatrically distributed in the western Hubei Province, have been used in traditional Chinese medicine (TCM) for about 2,000 years. Genetic variability and population genetic structure of 11 natural populations of these Epimedium species were investigated using isoelectric focusing in thin-layer polyacrylamide slab gels. Of the 22 enzyme systems prescreened, six coding for 13 loci and 45 alleles were resolved, which were used for analyzing genetic diversity and population structure at both intraspecific and interspecific levels. The results showed that: l) high levels of genetic diversity were observed in all three species (A = 2.6-3.2, P = 69.2%-84.6%, Ho= 0.274-0.377, HE= 0.282-0.369), which were higher than that of other herbaceous and aulmal-pollinated species with similar life-history characteristics; 2) there was significant deviation from Hardy-Weinberg Equilibrium, with one half of the loci showing heterozygote excess and the other homozygote excess, in all populations, suggesting the complicated breeding system of Epimedium species; 3) the low level of intraspecific and interspecific genetic differentiation (GST= 0.0246-0.0409 and 0.0495-0.1213, respectively) indicated a high level of gene flow among populations and close genetic relationship among the three species; and 4) UPGMA cluster analysis further showed that E. pubescens was more closely related to E. sagittatum than to E. wushanense, which was in good agreement with the morphological characters and the recent phylogenetic analysis of these species. On the basis of these results, it was concluded that the mixed breeding system, long-lived perennial life form, ancient evolutionary history, and seed dispersal by ants in Epimedium are responsible for the genetic variation and population structure of these species. 展开更多
关键词 Epimedium pubescens Maxim. E. sagittatum sieb. Zucc.) Maxim. E. wushanense T. s. Ying ALLOZYME genetic diversity population structure
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A study on deep structure using teleseismic receiver function in Western Yunnan 被引量:16
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作者 贺传松 王椿镛 吴建平 《地震学报》 CSCD 北大核心 2004年第3期238-246,共9页
s Western Yunnan is located at the boundary of collision or underthrusting zone of Eurasian plate and is influenced by many times tectonic movements. With very complex geological environment and tectonic background, i... s Western Yunnan is located at the boundary of collision or underthrusting zone of Eurasian plate and is influenced by many times tectonic movements. With very complex geological environment and tectonic background, it is one of the seismically active areas. In the paper, the teleseismic records were selected from 16 national, local and mo-bile stations, including 4 very-wide-band mobile stations of PASSCAL. And nearly 2 000 receiver functions were extracted. Two measuring lines are 650 km and 450 km, respectively and across some major tectonic units in Western Yunnan. It is indicated that Nujiang might be a seam characterized by underthrusting. The western and eastern boundaries of Sichuan-Yunnan rhombus block, i.e., Honghe and Xiaojiang faults, might be an erection seam or collision belt. Panxi tectonic zone still has the characteristics of continental rift valley, that is, the surface is hollow and the upper mantle is upwarping. The tectonic situation in Western Yunnan is of certain regulation with the interlacing distribution of orogenic zone and seam. The crustal thickness decreases gradually from the north to the south and the S wave velocity is globally lower here. 展开更多
关键词 接收函数 反演 s波速度结构 构造关系
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双金属MOFs碳化材料的结构对锂硫电池正极性能的影响 被引量:1
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作者 曹翔宇 张秀玲 +2 位作者 杜依洋 马成乡 闫娟枝 《化工新型材料》 CAS CSCD 北大核心 2024年第1期150-155,160,共7页
利用硝酸钴和铁氰化钾在水溶液中沉淀反应以及ZIF-8在水溶液中的部分分解,分别制备了2种组成相近但结构不同的双金属有机框架前驱体Co-Fe precursor和ZCF precursor。经过多巴胺包覆,对2种产品在氩气气氛下退火获得碳化产物。将碳化产... 利用硝酸钴和铁氰化钾在水溶液中沉淀反应以及ZIF-8在水溶液中的部分分解,分别制备了2种组成相近但结构不同的双金属有机框架前驱体Co-Fe precursor和ZCF precursor。经过多巴胺包覆,对2种产品在氩气气氛下退火获得碳化产物。将碳化产物与纳米硫粉混合得到的碳/硫复合材料(E-CoFeCN@C/S、E-ZCF@C/S)分别作为正极,组装扣式锂硫电池并测试电化学性能。利用X射线衍射仪、扫描电子显微镜、透射电子显微镜、热重分析仪进行形貌和结构分析。在组成相似的情况下,核壳结构碳载体(E-CoFeCN@C)与发散式结构碳载体(E-ZCF@C)对锂硫电池性能的影响呈现出“此消彼长”的特点:E-ZCF@C/S在循环伏安测试中表现出更小的极化以及更强的电流响应,在电化学阻抗测试中表现出更低的电荷转移阻抗,表明该材料有利于促进正极电荷传递过程,即加快电极反应动力学。E-ZCF@C/S在0.2C倍率下放电初始比容量为1211.3mAh/g,在2C倍率下放电初始比容量为794mAh/g,均优于E-CoFeCN@C/S。而核壳结构的优势主要体现在容量衰减方面,E-CoFeCN@C/S在0.2C倍率下经过100次循环后平均衰减率为0.074%(E-ZCF@C/S为0.26%),在2C倍率下循环300次后平均衰减率为0.047%(E-ZCF@C/S为0.13%),说明核壳结构对活性物质的锚固作用明显而对电荷转移不利。 展开更多
关键词 双金属MOFs 锂硫电池 材料结构 电化学性能
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HBsAg和HBsAb共存的慢性乙肝患者的血清学特征和S区突变位点
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作者 刘辉 郄恒宇 +1 位作者 刘新 娄金丽 《标记免疫分析与临床》 CAS 2024年第3期393-398,共6页
目的探讨HBsAg/HBsAb双阳患者和HBsAg单阳性患者的血清学差异,并对两组患者的HBV S区突变位点进行比较分析,探寻HBsAg/HBsAb共阳性患者可能的分子机制。方法选取首都医科大学附属北京佑安医院2022年6月至2023年3月的284例HBsAg/HBsAb双... 目的探讨HBsAg/HBsAb双阳患者和HBsAg单阳性患者的血清学差异,并对两组患者的HBV S区突变位点进行比较分析,探寻HBsAg/HBsAb共阳性患者可能的分子机制。方法选取首都医科大学附属北京佑安医院2022年6月至2023年3月的284例HBsAg/HBsAb双阳患者和519例HBsAg单阳患者,统计Age、ALT、AST、AST/ALT、TBiL、ALb、r-GT、HBsAg和HBsAg滴度、HBsAb、HBeAg、HBeAb、HBcAb、WBC,对两组患者的血清学指标进行比较分析。对HBV S区扩增成功的19例HBsAg/HBsAb双阳患者和19例HBsAg单阳患者进行测序分析,统计高频突变位点,分析HBV S区突变特征,探寻HBsAg/HBsAb双阳患者可能发生的分子机制。结果HBsAg/HBsAb双阳患者和HBsAg单阳患者在性别、HBeAg、ALT、AST、TBiL、r-GT差异有统计学意义(P<0.05)。两组患者在Age、HBeAb、HBcAb、AST/ALT、Alb、WBC差异无统计学意义(P>0.05)。HBsAg/HBsAb双阳组患者C基因型占78.95%(15/19),其中A113D/T、A317C/S、A45T、A86G、A87T、A96V、A97P等突变频率较高,HBsAg单阳组C基因型占84.21%(16/19),V159A、M47T、I213L、A317S、E44G、Q267L突变频率较高,两组患者的高频突变位点明显不同。结论双阳和单阳CHB患者血清学和基因突变位点存在显著差异。建议针对HBV S区不同的突变位点进一步研究HBsAg和HBsAb共存的机制。 展开更多
关键词 HBsAG 跨膜结构域 主要亲水区 s
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中强地震发震构造标志浅析——以2023年积石山M_(S)6.2地震为例
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作者 张军龙 徐岳仁 +1 位作者 李文巧 陈峰 《地震》 CSCD 北大核心 2024年第1期226-234,共9页
地震地表破裂是地震发生的重要特征,是研究地震动力学、构造变形的重要手段。一般认为,M6 3/4以上的地震才会形成地表破裂。但近年来,也有M6.0左右的地震发生了地表破裂。本文旨在探讨中强地震地表破裂的识别方法。中强地震发震构造的... 地震地表破裂是地震发生的重要特征,是研究地震动力学、构造变形的重要手段。一般认为,M6 3/4以上的地震才会形成地表破裂。但近年来,也有M6.0左右的地震发生了地表破裂。本文旨在探讨中强地震地表破裂的识别方法。中强地震发震构造的识别具有一定的挑战性,主要表现在以下几个方面:(1)中强地震地表破裂的规模(位错量、宽度、长度和深度)较小,容易被黄土层厚覆盖,掩盖地表破裂的痕迹,不易识别;(2)非构造成因裂缝干扰,使得难以区分构造成因地表破裂。本文以2023年积石山M_(S)6.2地震为例,对中强地震构造成因破裂的识别标志进行了初步分析,提出了以下识别标志:(1)地表破裂几何展布和剖面形态,地震伴生的次生灾害(滑坡、崩塌、砂土液化等)的线性分布为识别发震构造提供参考和线索;(2)地表破裂沿破裂走向呈现稳定地穿越不同地貌单元,至少穿越一条沟谷等低凹地貌;(3)地表破裂在地质剖面上表现出稳定的产状;(4)地表破裂伴生构造形态,地表沿破裂发育雁列式褶皱(挤压鼓包)与张裂缝交替出现的现象。本文提出的识别标志为中强地震发震构造的识别提供了新的思路。 展开更多
关键词 青藏高原 拉脊山断裂带 2023年积石山M_(s)6.2地震 发震构造 地震地表破裂
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纳米C-S-H/PCE对蒸养UHPC力学性能增强机理研究
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作者 伍勇华 易昂 +2 位作者 何娟 匡玉峰 原毅冰 《硅酸盐通报》 CAS 北大核心 2024年第8期2797-2805,共9页
目前超高性能混凝土(UHPC)制品的力学性能有待进一步提升,采用纳米C-S-H/PCE对UHPC进行增强在理论上是一种可行的技术途径。本文研究了蒸养条件下掺入以聚羧酸(PCE)为分散剂的纳米水化硅酸钙(C-S-H/PCE)对UHPC力学性能的影响,通过测试... 目前超高性能混凝土(UHPC)制品的力学性能有待进一步提升,采用纳米C-S-H/PCE对UHPC进行增强在理论上是一种可行的技术途径。本文研究了蒸养条件下掺入以聚羧酸(PCE)为分散剂的纳米水化硅酸钙(C-S-H/PCE)对UHPC力学性能的影响,通过测试水化热、水化产物、微观形貌和孔结构等对其机理进行了分析。结果表明,掺入3.0%(质量分数)纳米C-S-H/PCE可以显著提高蒸养UHPC的抗压强度和抗折强度。掺入纳米C-S-H/PCE可以促进UHPC的早期水化,生成更多的水化硅酸钙(C-S-H)凝胶,使水化放热温峰增高,并缩短达到水化温峰的时间。掺入纳米C-S-H/PCE可有效改善蒸养UHPC的孔结构,在掺量为3.0%(质量分数)时总孔隙率最小,有害孔比例最低。该研究可为纳米C-S-H/PCE在蒸养UHPC中的应用提供参考。 展开更多
关键词 纳米C-s-H/PCE 超高性能混凝土 孔结构 水化放热 蒸汽养护
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基于B/S的高校实验室预约管理系统设计与实现
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作者 李丹 《现代信息科技》 2024年第5期31-35,共5页
为了实现实验室管理信息化,更好地为师生服务,文章设计并开发一套高校实验室预约管理系统。该系统是基于B/S结构,采用Vue视图框架、Nginx服务器及MySQL数据库构建而成的;支持专业实验室、教室和会议室的预约管理;入口对接华中科技大学... 为了实现实验室管理信息化,更好地为师生服务,文章设计并开发一套高校实验室预约管理系统。该系统是基于B/S结构,采用Vue视图框架、Nginx服务器及MySQL数据库构建而成的;支持专业实验室、教室和会议室的预约管理;入口对接华中科技大学统一身份认证系统,在校师生可直接使用已有的统一身份认证系统账号密码登录系统。用户可通过浏览器完成在线预约、预约查询、预约管理和数据统计等功能。该系统的应用提高了实验室管理的规范性和信息化程度。 展开更多
关键词 预约管理 实验室信息化 B/s结构 MYsQL数据库
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Analysis of the Structure of Shakespeare's Sonnets
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作者 李鹏 《科技视界》 2014年第2期205-206,共2页
The sonnet is a kind of lyrics with restrict forms which cannot depart from the contents. Shakespeare's sonnets are like a valuable flower blossoming in the England poetry garden during the age of Renaissance and ... The sonnet is a kind of lyrics with restrict forms which cannot depart from the contents. Shakespeare's sonnets are like a valuable flower blossoming in the England poetry garden during the age of Renaissance and a bright pearl sparkling in the world's poetry treasury. This paper will analyze his sonnets from the perspective of the structure and then interpret the meanings behind those words, which can demonstrate the importance of the connection between the forms and the contents. 展开更多
关键词 英语教学 教学方法 阅读教学 课外阅读
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Effect of C/S Ratio on Morphology and Structure of Hydrothermally Synthesized Calcium Silicate Hydrate 被引量:11
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作者 何永佳 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第4期770-773,共4页
The samples of the C-S-H series were synthesized by hydrothermal reaction of fumed silica, CaO and deionized water at initial C/S ratios between 1.0-1.7. Phase composition and structural and morphology characteristics... The samples of the C-S-H series were synthesized by hydrothermal reaction of fumed silica, CaO and deionized water at initial C/S ratios between 1.0-1.7. Phase composition and structural and morphology characteristics of C-S-H samples were analyzed by XRD, IR and SEM. The experimental results showed that the d-spacing of (002), (110) and (020) decreased, the d-spacing of (200) increased, and the d-spacing of (310) varied randomly, the polymerization of silica tetrahedra of C-S-H decreased, and morphology of C-S-H samples varied from sheet shapes to long reticular fibers as C/S ratio increased. 展开更多
关键词 calcium silicate hydrate C/s ratio MORPHOLOGY structure hydrothermal synthesis
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A welding document management software package based on a Client/Server structure 被引量:4
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作者 魏艳红 杨春利 王敏 《China Welding》 EI CAS 2003年第1期72-77,共6页
According to specifications for Welding Procedure Qualification of ASME IX Section and Chinese code, JB 4708 2000, a software package for managing welding documents has been rebuilt. Consequently, the new software pa... According to specifications for Welding Procedure Qualification of ASME IX Section and Chinese code, JB 4708 2000, a software package for managing welding documents has been rebuilt. Consequently, the new software package can be used in a Limited Area Network (LAN) with 4 different levels of authorities for different users. Therefore, the welding documents, including DWPS (Design for Welding Procedure Specifications), PQRs (Procedure Qualification Records) and WPS (Welding Procedure Specifications) can be shared within a company. At the same time, the system provides users various functions such as browsing, copying, editing, searching and printing records, and helps users to make decision of whether a new PQR test is necessary or not according to the codes above as well. Furthermore, super users can also browse the history of record modification and retrieve the records when needed. 展开更多
关键词 C/s structure welding procedure qualification DATABAsE LAN
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A study on deep structure using teleseismic receiver function in Western Yunnan 被引量:2
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作者 HE Chuan-song(贺传松) +3 位作者 WANG Chun-yong(王椿镛) WU Jian-ping(吴建平) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第3期262-271,共10页
s Western Yunnan is located at the boundary of collision or underthrusting zone of Eurasian plate and is influenced by many times tectonic movements. With very complex geological environment and tectonic background, i... s Western Yunnan is located at the boundary of collision or underthrusting zone of Eurasian plate and is influenced by many times tectonic movements. With very complex geological environment and tectonic background, it is one of the seismically active areas. In the paper, the teleseismic records were selected from 16 national, local and mo-bile stations, including 4 very-wide-band mobile stations of PASSCAL. And nearly 2 000 receiver functions were extracted. Two measuring lines are 650 km and 450 km, respectively and across some major tectonic units in Western Yunnan. It is indicated that Nujiang might be a seam characterized by underthrusting. The western and eastern boundaries of Sichuan-Yunnan rhombus block, i.e., Honghe and Xiaojiang faults, might be an erection seam or collision belt. Panxi tectonic zone still has the characteristics of continental rift valley, that is, the surface is hollow and the upper mantle is upwarping. The tectonic situation in Western Yunnan is of certain regulation with the interlacing distribution of orogenic zone and seam. The crustal thickness decreases gradually from the north to the south and the S wave velocity is globally lower here. 展开更多
关键词 receiver function INVERsION s wave velocity structure tectonic relationship
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Dinuclear Copper(Ⅱ) Complex with a New Polycarboxylate Ligand:Syntheses,Characterization and Crystal Structure 被引量:2
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作者 沈超君 盛天录 +5 位作者 傅瑞标 胡胜民 陈建珊 朱起龙 马骁 吴新涛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第1期11-18,共8页
A dinuclear copper(Ⅱ) complex,[Cu2(HL)2(H2O)6] 1(H3L = 2,4,6-tri(3-carboxy-phenylthio)-1,3,5-triazine),was synthesized hydrothermally and characterized by single-crystal X-ray diffraction,IR and thermal ana... A dinuclear copper(Ⅱ) complex,[Cu2(HL)2(H2O)6] 1(H3L = 2,4,6-tri(3-carboxy-phenylthio)-1,3,5-triazine),was synthesized hydrothermally and characterized by single-crystal X-ray diffraction,IR and thermal analysis.Single-crystal X-ray diffraction reveals that complex 1 is a dinuclear copper(Ⅱ) complex,which is further extended to a 3D network by weak interactions such as O…H-O hydrogen bonds and noncovalent S...S interactions.The crystal of compound 1 belongs to monoclinic,space group C2/c,with a = 50.15(2),b = 6.789(3),c =15.667(8) ,β = 90.588(9)o,V = 5334(4) 3,Z = 4,C48H38Cu2N6O18S6,Mr = 1306.28,Dc = 1.627 g/cm3,F(000) = 2664,Rint = 0.0631,T = 293(2) K,μ = 1.112 mm-1,the final R = 0.0661 and wR = 0.1850 for 3782 observed reflections with I 2σ(I). 展开更多
关键词 COPPER crystal structure hydrogen bonds noncovalent ss interactions
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绿色信贷政策、ESG表现与高污染企业资本结构调整 被引量:3
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作者 董越 潘海英 《资源与产业》 2024年第1期75-85,共11页
绿色信贷政策作为结构性去杠杆的重要举措,对于高污染企业资本结构升级大有裨益。与此同时,ESG概念的提出明确了企业发展需着重考量环境(E)、社会(S)和公司治理(G)三方面的表现,即企业ESG表现也将作用于高污染企业资本结构调整。因此,... 绿色信贷政策作为结构性去杠杆的重要举措,对于高污染企业资本结构升级大有裨益。与此同时,ESG概念的提出明确了企业发展需着重考量环境(E)、社会(S)和公司治理(G)三方面的表现,即企业ESG表现也将作用于高污染企业资本结构调整。因此,论文以2011—2020年中国A股上市的高污染企业为研究样本,基于ESG表现视角,探究绿色信贷政策对高污染企业资本结构调整的作用效果。研究表明:1)绿色信贷政策显著促进高污染企业资本结构调整,区分企业负债水平后发现,相比于低负债企业,绿色信贷政策显著加快高负债污染企业的资本结构调整速度;2)绿色信贷政策会提升高污染企业的ESG表现,企业ESG表现会削弱绿色信贷政策对高污染企业资本结构调整的促进效果;3)在深入探讨企业融资约束和商业信用程度的异质性是否会影响绿色信贷政策的实施效果时,发现相较于面临弱融资约束和拥有高商业信用的企业,绿色信贷政策显著促进面临强融资约束和低商业信用的高污染企业调整资本结构。因此,探讨绿色信贷政策与高污染企业资本结构调整的关系对优化信贷资源配置、推动高污染企业绿色转型意义重大。 展开更多
关键词 绿色信贷政策 资本结构调整 企业EsG表现 高污染企业
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Spatial distribution characteristics of bacterial community structure and gene abundance in sediments of the Bohai Sea 被引量:3
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作者 Quanrui Chen Jingfeng Fan +10 位作者 Jie Su Hongxia Ming Zhihao Sun Mengfei Li Xiaohui Zhao Yantao Wang Yingxue Zhang Huizhen Zhang Yuan Jin Xiaowan Ma Bin Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第2期69-78,共10页
This study investigated differences in the community structure and environmental responses of the bacterial community in sediments of the Bohai Sea.Illumina high-throughput sequencing technology and real-time PCR were... This study investigated differences in the community structure and environmental responses of the bacterial community in sediments of the Bohai Sea.Illumina high-throughput sequencing technology and real-time PCR were used to assay the bacterial 16S rRNA genes in the surface sediments of 13 sampling stations in the Bohai Sea.The results showed that sediments at the majority of the 13 sampling stations were contaminated by heavy metal mercury.The main phyla of bacteria recorded included Proteobacteria(52.92%),Bacteroidetes(11.76%),Planctomycetes(7.39%),Acidobacteria(6.53%)and Chloroflexi(4.97%).The genus with the highest relative abundance was Desulfobulbus(4.99%),which was the dominant genus at most sampling stations,followed by Lutimonas and Halioglobus.The main factors influencing bacterial community structure were total organic carbon,followed by depth and total phosphorus.The content of lead,cadmium,chromium,copper and zinc had a consistent effect on community structure.Arsenic showed a negative correlation with bacterial community structure in most samples,while the impact of mercury on community structure was not significant.The bacterial community in sediment samples from the Bohai Sea was rich in diversity and displayed an increase in diversity from high to low latitudes.The data indicated that the Bohai Sea had abundant microbial resources and was rich in bacteria with the potential to metabolize many types of pollutants. 展开更多
关键词 Bohai sea sEDIMENTs bacterial community structure HIGH-THROUGHPUT sequencing 16s RRNA GENE
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