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多梁式波形钢腹板工字钢组合梁荷载横向分布系数研究

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计算力学学报 2024年第3期41卷 483-490页

作者：吴传山邓文琴张焕涛查上张建东山东高速济青中线公路有限公司潍坊261516 南京工业大学土木工程学院南京211816 苏交科集团股份有限公司南京211112

为探讨多梁式波形钢腹板工字钢组合梁横向分布系数计算方法,同时考虑波形钢腹板抗扭刚度、剪切变形及钢混滑移效应,对传统的偏心压力法、修正偏心压力法及刚接梁法进行修正,并结合有限元模型通过一座典型的4主梁波形钢腹板工字钢组合梁... 详细信息

为探讨多梁式波形钢腹板工字钢组合梁横向分布系数计算方法,同时考虑波形钢腹板抗扭刚度、剪切变形及钢混滑移效应,对传统的偏心压力法、修正偏心压力法及刚接梁法进行修正,并结合有限元模型通过一座典型的4主梁波形钢腹板工字钢组合梁桥对比分析了上述方法的适用性,最后基于参数分析研究了横隔板数量及刚度对其横向荷载分布系数的影响。结果表明,考虑剪切变形及滑移效应的刚接梁法得到的荷载横向分布系数与有限元值符合最好;当桥梁宽跨比小于2时,宜采用刚接梁法计算各主梁荷载横向分布系数,当宽跨比大于2时,宜采用更为简洁的修正偏心压力法进行计算;横隔板的设置可改善各主梁荷载横向均匀分布,但跨间横隔板间距和刚度对其荷载横向分布系数影响较小,实桥设计时可仅在端部及跨中位置布置横隔板,横隔板刚度及其余部位横隔板数量可根据结构稳定性要求进行布置。

关键词：钢混组合梁波形钢腹板工字钢梁荷载横向分布系数剪切变形滑移效应横隔板

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不同干燥方法对合欢花药材化学成分及其抗氧化活性影响

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天然产物研究与开发 2024年第1期36卷 125-136页

作者：左亚锋徐秀泉李巧月王孟虎孟祥松闫攀金传山吴德玲亳州学院中药学院亳州学院中药原料产品研发安徽普通高校重点实验室亳州236800 安徽中医药大学药学院合肥230012

建立测定合欢花药材中槲皮苷、异槲皮苷和槲皮素3种黄酮类成分含量测定的方法。通过化学成分含量及其抗氧化活性测定,探讨不同干燥方法对不同规格合欢花药材的影响,为合欢花药材的初加工工艺选择提供参考。通过晒干、阴干、蒸汽杀青后... 详细信息

建立测定合欢花药材中槲皮苷、异槲皮苷和槲皮素3种黄酮类成分含量测定的方法。通过化学成分含量及其抗氧化活性测定,探讨不同干燥方法对不同规格合欢花药材的影响,为合欢花药材的初加工工艺选择提供参考。通过晒干、阴干、蒸汽杀青后烘干、微波杀青后烘干、烘干(30、50、70、90℃)、冷冻干燥的方式对两种规格合欢花药材进行干燥处理,采用紫外分光光度法、高效液相色谱法、比色法和ABTS法、DPPH法等检测样品中总黄酮、异槲皮苷、槲皮苷、槲皮素含量及抗氧化活性。利用主成分分析、聚类分析和相关性分析对干燥后不同规格样品进行综合评价。研究结果表明,不同干燥处理合欢花药材样品化学成分和抗氧化活性结果存在显著差异。相关性分析表明,槲皮苷含量和总黄酮含量呈显著正相关(P<0.05),槲皮苷含量可作为总黄酮含量大小的评价指标,与O_(2)^(-)自由基清除能力呈正相关但不显著。槲皮苷含量和总黄酮含量与其他四种抗氧化指标呈显著正相关(P<0.05)或极显著正相关(P<0.01),槲皮素含量与ABTS自由基清除能力呈显著正相关(P<0.05),推测槲皮苷和槲皮素是2种合欢花类药材主要抗氧化活性物质。不同干燥方法对2种规格合欢花药材影响显著,盛开的合欢花适合宜采用70℃烘干处理,花蕾期的合欢米宜采用冷冻干燥处理,合欢花和合欢米均不宜采用阴干处理。本研究为2种合欢花类药材初加工方法的选择提供实验依据。

关键词：合欢花干燥方法化学成分抗氧化活性

Metallocorrole-based porous organic polymers as a heterogeneous catalytic nanoplatform for efficient carbon dioxide conversion

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Nano Research 2022年第2期15卷 1145-1152页

作者： Yanming Zhao Yunlei Peng chuan shan Zhou Lu Lukasz Wojtas Zhenjie Zhang Bao Zhang Yaqing Feng Shengqian Ma School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Department of Chemistry University of North TexasDentonTexas 76201USA College of Chemistry Nankai UniversityTianjin 300071China Department of Chemistry University of South FloridaTampaFlorida 33620USA Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072China

Metallocorrole macrocycles that represent a burgeoning class of attractive metal-complexes from the porphyrinoid family,have attracted great interest in recent years owing to their unique structure and excellent performance revealed in many fields,yet further functionalization through incorporating these motifs into porous nanomaterials employing the bottom-up approach is still scarce and remains synthetically ***,we report the targeted synthesis of porous organic polymers(POPs)constructed from custom-designed Mn and Fe-corrole complex building units,respectively denoted as CorPOP-1(Mn)and CorPOP-1(FeCl).Specifically,the robust CorPOP-1(Mn)bearing Mn-corrole active centers displays superior heterogeneous catalytic activity toward solvent-free cycloaddition of carbon dioxide(CO_(2))with epoxides to form cyclic carbonates under mild reaction conditions as compared with the homogeneous ***-1(Mn)can be easily recycled and does not show significant loss of reactivity after seven successive *** work highlights the potential of metallocorrole-based porous solid catalysts for targeting CO_(2) transformations,and would provide a guide for the task-specific development of more corrole-based multifunctional materials for extended applications.

关键词： corrole porphyrinoid derivatives heterogenization porous organic polymers(POPs) CO_(2)conversion heterogeneous catalysis

Triggering triplet excitons of carbon nanodots through nanospace domain confinement for multicolor phosphorescence in aqueous solution

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Nano Research 2024年第7期17卷 6534-6543页

作者： Ya-chuan Liang Qing Cao Yuan Deng Yong Wang Kai-Kai Liu Chong-Xin shan School of Electronics and Information Zhengzhou University of Light IndustryZhengzhou 450002China Henan Key Laboratory of Diamond Optoelectronic Material and Devices Key Laboratory of Material PhysicsMinistry of EducationSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450001China Academy for Quantum Science and Technology Zhengzhou University of Light IndustryZhengzhou 450002China Institute of Quantum Materials and Physics Henan Academy of SciencesZhengzhou 450046China

Easy non-radiative decay property of long-lived triplet excitons in aqueous solution obstructs their applications in aquatic *** reported phosphorescence phenomena in aqueous solution have excited researchers enormously but achieving full-color water-soluble phosphorescent carbon nanodots(CNDs)is still a challenging ***,full-color phosphorescence of water-soluble CNDs has been demonstrated by triggering their triplet excitons through nanospace domain confinement,and Förster energy resonance transfer is used for further tuning phosphorescence *** phosphorescence spans across most of the visible spectrum,ranging from 400 to 700 *** an aqueous solution,the CNDs exhibits blue,green,and red phosphorescence,lasting for approximately 6,10,and 7 s,***,the phosphorescence quantum yields are 11.85%,8.6%and 3.56%,making them readily discernible to the naked eyes and laying a solid foundation for practical ***,phosphorescence flexible optical display and bioimaging have been demonstrated by using the multicolor CNDs-based nanomaterials,showing distinct superiority for accuracy and complete display and imaging in complex emission background.

关键词： carbon nanodots triplet excitons multicolor aqueous solution

Linear stability of a fluid channel with a porous layer in the center

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Acta Mechanica Sinica 2014年第1期30卷 28-36页

作者： Qi Li Hai-Yan Lei chuan-shan Dai School of Mechanical Engineering Tianjin University Key Laboratory of Efcient Utilization of Low and Medium Grade Energy MOETianjin University

We perform a Poiseuille flow in a channel linear stability analysis of a inserted with one porous layer in the centre, and focus mainly on the effect of porous filling ratio. The spectral collocation technique is adopted to solve the coupled linear stability problem. We investigate the effect of permeability, σ, with fixed porous filling ratio ψ = 1/3 and then the effect of change in porous filling ratio. As shown in the paper, with increasing σ, almost each eigenvalue on the upper left branch has two subbranches at ψ = 1/3. The channel flow with one porous layer inserted at its middle （ψ = 1/3） is more stable than the structure of two porous layers at upper and bottom walls with the same parameters. By decreasing the filling ratio ψ, the modes on the upper left branch are almost in pairs and move in opposite directions, especially one of the two unstable modes moves back to a stable mode, while the other becomes more instable. It is concluded that there are at most two unstable modes with decreasing filling ratio ψ. By analyzing the relation between ψ and the maximum imaginary part of the streamwise phase speed, Cimax, we find that increasing Re has a destabilizing effect and the effect is more obvious for small Re, where ψ a remarkable drop in Cimax can be observed. The most unstable mode is more sensitive at small filling ratio ψ, and decreasing ψ can not always increase the linear stability. There is a maximum value of Cimax which appears at a small porous filling ratio when Re is larger than 2 000. And the value of filling ratio 0 corresponding to the maximum value of Cimax in the most unstable state is increased with in- creasing Re. There is a critical value of porous filling ratio （= 0.24） for Re = 500; the structure will become stable as ψ grows to surpass the threshold of 0.24; When porous filling ratio ψ increases from 0.4 to 0.6, there is hardly any changes in the values of Cimax. We have also observed that the critical Reynolds number is especially sen

关键词： Porous layer Linear stability Porous filling ratio Poiseuille flow Interface

Construction of clinical research nurse training program based on position competence

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World Journal of Clinical Cases 2023年第30期11卷 7363-7371页

作者： Jie Sun Wen-chuan shan Jun-Mei Liu Qin-Qin Zhang Yi Ye Shu-Ting Huang Keng Zhong Department of Nursing The First Affiliated Hospital of Naval Medical UniversityShanghai 200433China Department of Outpatient The First Affiliated Hospital of Naval Medical UniversityShanghai 200433China Department of Cardiology Surgery The First Affiliated Hospital of Naval Medical UniversityShanghai 200433China Reproductive Center The First Affiliated Hospital of Naval Medical UniversityShanghai 200433China Department of Cardiovascular Surgery The First Affiliated Hospital of Naval Medical UniversityShanghai 200433China

BACKGROUND As one of the most important members in clinical trials,the number of clinical research nurses(CRN)can't keep up with the growth of experimental projects,so it is urgent to build clinical research training and strengthen the background knowledge of *** To construct CRN training program based on position competence,accelerate the construction of CRN talent pool,and provide scientific guidance significance for CRN *** Based on the position competence model,combined with literature research and qualitative interview results,the first draft was prepared of the CRN training *** rounds of correspondence with 16 experts were conducted using the Delphi method to determine the training *** The effective recovery rate of the expert correspondence questionnaire was 100%and the authority coefficients of the 2 rounds of experts were 0.826 and ***,4 first-level indicators and determine 15 s-level indicators of training *** training program included 4 first-level indicators,training requirements,content,methods,assessment and evaluation,15 s-level indicators,and 74 third-level *** The CRN training program based on position competence is scientific and extendable,providing a basis for participation in CRN training.

关键词： Research nurses Position competence Training program Delphi method

Steroid hormone 20-hydroxyecdysone disturbs fat body lipid metabolism and negatively regulates gluconeogenesis in Hyphantria cunea larvae

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Insect Science 2023年第3期30卷 771-788页

作者： Sheng-Yu Zhang Han Gao Ankarjan Askar Xing-Peng Li Guo-Cai Zhang Tian-Zhong Jing Hang Zou Hao Guan Yun-He Zhao chuan-shan Zou School of Forestry Northeast Forestry UniversityHarbinChina Beiua University JilinChia

The steroid hormone 20-hydroxyecdysone(20E)has been described to regulate fat body lipid metabolism in insects,but its accurate regulatory mechanism,especially the crosstalk between 20E-induced lipid metabolism and gluconeogenesis remains largely ***,we specially investigated the effect of 20E on lipid metabolism and gluconeogenesis in the fat body of Hyphantria cunea larvae,a notorious pest in *** analysis showed that a total of 1907 lipid species were identified in the fat body of *** larvae assigned to 6 groups and 48 lipid *** differentially abundant lipids analysis showed a significant difference between 20E-treated and control samples,indicating that 20E caused a remarkable alteration of lipidomics profiles in the fat body of *** *** studies demonstrated that 20E accelerated fatty acidβ-oxidation,inhibited lipid synthesis,and promoted ***,the activities of pyruvate carboxylase,phosphoenolpyruvate carboxykinase,fructose-1,6-bisphosphatase,and glucose-6-phosphatase were dramatically suppressed by 20E in the fat body of *** *** well,the transcriptions of genes encoding these 4 rate-limiting gluconeogenic enzymes were significantly downregulated in the fat body of *** larvae after treatment with *** together,our results revealed that 20E disturbed fat body lipid homeostasis,accelerated fatty acidβ-oxidation and promoted lipolysis,but negatively regulated gluconeogenesis in *** *** findings might provide a new insight into hormonal regulation of glucose and lipid metabolism in insect fat body.

关键词： 20-hydroxyecdysone Hyphantria cunea fat body lipidomics analysis lipid metabolism gluconeogenesis

Synthesis of CdTe/SiO_2 Composites and Their Fluorescence Properties

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Chemical Research in Chinese Universities 2011年第4期27卷 540-542页

作者： WANG Mei-ping LIN Jin-hui shan chuan-sheng College of Materials and Chemistry ＆ Chemical Engineering Chengdu University of Technology Chengdu 610059 P. R. China

Thioglycolic acid（TGA）-stabilized CdTe nanocrystals（NCs） were prepared with sodium tellurite as tellurium source,which avoids the cumbersome processes associated with H2Te or NaHTe *** CdTe/SiO2 composites were synthesized by a sol-gel method without the exchange of surface *** phase structure of CdTe NCs was investigated by X-ray *** comparison,some characterizations were done for both the CdTe NCs and the *** NCs and CdTe/SiO2 composites were characterized with TEM,digital camera and fluorescence *** stability of CdTe NCs and the composites were investigated in phosphate-buffered saline（PBS） buffer and the fluorescent properties of the composites were discussed in detail.

关键词： CdTe nanocrystal Sodium tellurite CdTe/SiO2

LAG3分子对泡球蚴感染小鼠肝脏B淋巴细胞亚群及其功能的影响

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中国人兽共患病学报 2024年第6期40卷 529-536页

作者：郑旭然邓冰清康雪娇李寅时阿比旦·艾尼瓦尔余倩孜比姑·肉素阿迪莱·多力坤王茂林王慧张传山李静新疆医科大学基础医学院乌鲁木齐830054 新疆医科大学第一附属医院临床医学研究院、省部共建中亚高发病成因与防治国家重点实验室、新疆维吾尔自治区包虫病基础医学重点实验室乌鲁木齐830054 新疆地区高发疾病研究教育部重点实验室(新疆医科大学) 乌鲁木齐830054 新疆维吾尔自治区地方病分子生物学重点实验室乌鲁木齐830054

目的探究淋巴细胞活化基因-3(Lymphocyte activation gene-3,LAG3)分子对泡球蚴感染小鼠肝脏B淋巴细胞亚群及其功能的影响。方法将野生型(C57-wild-type, WT)和LAG3基因敲除(LAG3-knockout, LAG3-KO)小鼠经肝门静脉注射泡球蚴原头节,... 详细信息

目的探究淋巴细胞活化基因-3(Lymphocyte activation gene-3,LAG3)分子对泡球蚴感染小鼠肝脏B淋巴细胞亚群及其功能的影响。方法将野生型(C57-wild-type, WT)和LAG3基因敲除(LAG3-knockout, LAG3-KO)小鼠经肝门静脉注射泡球蚴原头节,感染12周免疫组织化学染色观察小鼠肝脏CD19和α-SMA表达及定位,流式细胞术检测小鼠肝脏B细胞及其各亚群和表面CD80、CD86、MHC-Ⅱ分子的表达情况。结果泡球蚴感染12周小鼠肝脏LAG3-KO组CD19阳性区及面积占比略高于WT组,但差异均无统计学意义。α-SMA在LAG3-KO组阳性区及面积占比显著高于WT组(t=-3.224、-3.227,P均<0.05)。LAG3-KO组肝脏B细胞表达CD80和MHC-Ⅱ分子的比例显著上调,差异具有统计学意义(t=-2.379、-3.321,P均<0.05)。LAG3-KO组B2细胞占比显著高于WT组,差异有统计学意义(t=-2.695,P<0.05)。LAG3-KO组B1b细胞表达CD80比例亦显著上调,差异具有统计学意义(t=-5.315,P<0.001),而B2细胞表达CD80比例显著低于WT组,且差异具统计学意义(t=2.806,P<0.05)。LAG3-KO组B2细胞表达MHC-Ⅱ分子显著上调,且具统计学差异(t=-4.227,P<0.01)。结论泡球蚴感染中期12周,LAG3分子影响小鼠肝脏B细胞亚群及功能,并以B2型淋巴细胞尤为显著,LAG3对B细胞的活化以及MHC-Ⅱ类分子表达产生抑制作用,提示其可能参与泡球蚴感染下的B细胞耗竭。

关键词：泡球蚴淋巴细胞活化基因-3 B细胞 B细胞亚群

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