检索结果-南通市图书馆

Chinese Journal of Structural Chemistry 2019年第6期38卷 901-908页

作者： XU yun DING fang LIU Dong yang Pei-Pei College of Chemistry and Materials Science Huaibei Normal University

Two new coordination polymers, [Cd(BDC)(HL)]n(I) and {[Zn(BDC)(HL)2]·(H2 O)}n(Ⅱ), have been synthesized under solvothermal conditions, based on 1 H-pyrazolo[3,4-b]pyridin-3-amine(HL) along with 1,4-benzenedicarboxylic acid(H2 BDC). Polymers I and Ⅱ have been characterized by elemental analysis, IR spectroscopy, powder X-ray diffraction(PXRD) and single-crystal X-ray diffraction analysis. Polymer I features a two-dimensional 4-connected sql structure and further extends into a three-dimensional supramolecular framework directed by hydrogen-bonding interactions and π-π interactions. Polymer Ⅱ exhibits a layered packing supramolecular structure. Hydrogen bonding interactions involved between the free water molecules and carboxylate O atoms of H2 BDC ligands as well as the amino N atom of HL ligands play a critical role in constructing the three-dimensional supramolecular structure of Ⅱ. The solid-state photoluminescent properties of the two polymers were also investigated.

关键词： 1H-pyrazolo[3,4-b]pyridin-3-amine supramolecular structure hydrogen-bonding interactions

在线全文

学校读者我要写书评

暂无评论

10个品种波斯菊表型多样性分析

华北理工大学学报（自然科学版） 2025年第1期47卷 23-32页

作者：孙桂芳杨建伟刘冬云河北农业大学园林与旅游学院河北保定071000 兴隆县住房和城乡建设局河北兴隆067300 兴隆县城市管理综合行政执法局河北兴隆067300

以10个品种波斯菊的物候期、生长动态及22个表型性状为指标,进行物种变异和遗传多样性的分析,并对其进行聚类分析,以探究其亲缘关系。结果表明:(1)波斯菊不同品种的物候期存在明显差异;(2)各品种生长过程遵循‘S’曲线;(3)通过对其20个... 详细信息

以10个品种波斯菊的物候期、生长动态及22个表型性状为指标,进行物种变异和遗传多样性的分析,并对其进行聚类分析,以探究其亲缘关系。结果表明:(1)波斯菊不同品种的物候期存在明显差异;(2)各品种生长过程遵循‘S’曲线;(3)通过对其20个数量性状进行表型性状的变异分析可知,波斯菊各品种表型差异主要表现在花色、花梗长、每果实结籽数、冠幅、着花量等性状;(4)聚类分析将波斯菊分为2个大类:‘白雪公主’、‘白丝袜’和‘花季’为1类,此类株高相对低矮,花梗长、叶面积较小,每果实结籽数较大、花色明度较高且色调简单;其余7个品种‘阿波罗’(粉渐变)、‘栗黄’、‘海贝’、‘闺蜜’、‘梦之蓝’、‘玫红’和‘海蓝之星’为1类。总之,研究表明波斯菊各品种具有广泛的变异和丰富的遗传多样性。

关键词：波斯菊表型性状变异遗传多样性聚类分析

维普期刊数据库博看期刊

Synthesis, Structure and Properties of a New Terbium(Ⅲ) Complex Tb2(C15H11O3)6(phen)2

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2020年第7期39卷 1087-1092页

作者： yang Ying-Qun LI Wei yang Pin-fang KUANG yun-Fei Key Laboratory of Functional Metal-organic Compounds of Hunan Province&Key Laboratory of Functional Organometallic Materials University of Hunan ProvinceHengyang 421008China Department of Chemistry and Materials Science Hengyang Normal UniversityHengyang 421008China

A new terbium(Ⅲ) complex Tb2(C15H11O3)6(phen)2 has been synthesized with 2-(4-methylbenzoyl)benzoic acid and 1,10-phenanthroline as *** data for the complex are as follows:monoclinic,space group P21/n,a=15.0786(6),b=13.5762(5),c=22.9683(9) A,β=104.130(4)°,V=4559.6(3) A3,Dc=1.540g/cm3,Z=2,μ(MoKα)=1.615 mm-1,F(000)=2136,the final R=0.0528 and wR=*** Tb(Ⅲ) ion is coordinated by eight atoms to give a distorted square antiprism coordination *** complex shows four fluorescence emission bands arising from the transitions of Tb3+5D4→7F6(490 nm),5D4→7F5(546 nm),5D4→7F4(588 nm) and 5D4→7F3(622 nm).The complex is an antiferromagnet in the range of 300~2 *** reported in the paper is the thermal stability property of the title complex.

关键词： terbium(Ⅲ)complex crystal structure fluorescence and magnetic properties

同方期刊数据库

单轴应变对本征和N掺杂4H-SiC电子结构的影响

在线全文

学校读者我要写书评

暂无评论

原子与分子物理学报 2025年第3期42卷 173-179页

作者：秦彦军张建强杨慧雅方峥范晓珍邝富丽叶慧群方允樟浙江师范大学物理与电子信息工程学院金华321004 新疆理工学院理学院阿克苏843100 浙江旅游职业学院杭州311231

采用基于密度泛函理论的第一性原理方法,研究了单轴应变对本征和N掺杂4H-SiC电子结构的影响.研究表明应变可以有效调控本征和N掺杂4H-SiC的带隙,在拉应变作用下,带隙单调减小;而在压应变作用下,带隙先增大后减小,当压应变为-1%时,带隙... 详细信息

采用基于密度泛函理论的第一性原理方法,研究了单轴应变对本征和N掺杂4H-SiC电子结构的影响.研究表明应变可以有效调控本征和N掺杂4H-SiC的带隙,在拉应变作用下,带隙单调减小;而在压应变作用下,带隙先增大后减小,当压应变为-1%时,带隙达到最大值.对态密度的分析可知本征和N掺杂4H-SiC的价带顶主要来自Si 3p和C 2p态电子,导带底主要来自Si 3p态电子,C 2p态和Si 3p态通过影响价带顶和导带底从而导致应变结构中带隙发生变化.通过Mulliken布局和差分电荷密度分析可知,随着晶格常数的增加Si原子向C原子和N原子转移的电荷减少,同时Si-C原子和Si-N原子之间的共价性减弱.

关键词： 4H-SiC 单轴应变电子结构第一性原理

维普期刊数据库博看期刊

A Tensor Neural Network with Layerwise Pretraining： Towards Effective Answer Retrieval

在线全文

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2016年第6期31卷 1151-1160页

作者： Xin-Qi Bao yun-fang Wu Key Laboratory of Computational Linguistics Peking University Beijing 100871 China

In this paper we address the answer retrieval problem in community-based question answering. To fully capture the interactions between question-answer pairs, we propose an original tensor neural network to model the relevance between them. The question and candidate answers are separately embedded into different latent semantic spaces, and a 3-way tensor is then utilized to model the interactions between latent semantics. To initialize the network layers properly, we propose a novel algorithm called denoising tensor autoencoder （DTAE）, and then implement a layerwise pretraining strategy using denoising autoencoders （DAE） on word embedding layers and DTAE on the tensor layer. The experimental results show that our tensor neural network outperforms various baselines with other competitive neural network methods, and our pretraining DTAE strategy improves the system＇s performance and robustness.

关键词： artificial intelligence language parsing and understanding machine learning

Hub genes and key pathways of traumatic brain injury: bioinformatics analysis and in vivo validation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2020年第12期15卷 2262-2269页

作者： yun-Liang Tang Long-Jun fang Ling-yang Zhong Jian Jiang Xiao-yang Dong Zhen Feng Department of Rehabilitation Medicine The First Affiliated Hospital of Nanchang UniversityNanchangJiangxi ProvinceChina

The exact mechanisms associated with secondary brain damage following traumatic brain injury(TBI)remain unclear;therefore,identifying the critical molecular mechanisms involved in TBI is *** m RNA expression microarray GSE2871 was downloaded from the Gene Expression Omnibus(GEO)***2871 comprises a total of 31 cerebral cortex samples,including two post-TBI time *** microarray features eight control and seven TBI samples,from 4 hours post-TBI,and eight control and eight TBI samples from 24 hours *** this bioinformatics-based study,109 and 66 differentially expressed genes(DEGs)were identified in a Sprague-Dawley(SD)rat TBI model,4 and 24 hours post-TBI,*** enrichment analysis showed that the identified DEGs were significantly enriched in several terms,such as positive regulation of nuclear factor-κB transcription factor activity,mitogen-activated protein kinase signaling pathway,negative regulation of apoptotic process,and tumor necrosis factor signaling ***,the hub genes with high connectivity degrees were primarily related to inflammatory *** validate the top five hub genes,a rat model of TBI was established using the weight-drop method,and real-time quantitative polymerase chain reaction analysis of the cerebral cortex was *** results showed that compared with control rats,Tnf-α,c-Myc,Spp1,Cxcl10,Ptprc,Egf,Mmp9,and Lcn2 were upregulated,and Fn1 was downregulated in TBI *** these hub genes,Fn1,c-Myc,and Ptprc may represent novel biomarkers or therapeutic targets for *** identified pathways and key genes may provide insights into the molecular mechanisms of TBI and provide potential treatment targets for patients with *** study was approved by the Experimental Animal Ethics Committee of the First Affiliated Hospital of Nanchang University,China(approval No.003)in January 2016.

关键词： bioinformatics DEGs differentially expressed genes Gene Ontology hub genes inflammation Kyoto Encyclopedia of Genes and Genomes molecular mechanism traumatic brain injury

The neuroprotective effect of mesenchymal stem cells is mediated through inhibition of apoptosis in hypoxic ischemic injury

在线全文

学校读者我要写书评

暂无评论

World Journal of Pediatrics 2020年第2期16卷 193-200页

作者： fang Li Kun Zhang Hua Liu Tan yang Dong-Jie Xiao yun-Shan Wang Laboratory of Cell Therapy and Translational Medicine Jinan Central Hospital Affiliated to Shandong University105 Jiefang RoadJinan 250013China Shandong Research Center of Transplantation and Tissue Jinan 250013China Clinical Laboratory The People's Hospital of BozhouBozhou 236800China

Background Neonatal hypoxia ischemia causes severe brain *** cell therapy is a promising method for treating neuronal *** translation of human umbilical cord-derived mesenchymal stem cells(UC-MSCs)for the recovery of neurons after hypoxic ischemic encephalopathy(HIE)may represent an effective *** Primary neurons were exposed to oxygen-glucose deprivation(OGD)and subsequently cocultured with *** was examined by Annexin *** related to apoptosis were detected using RT-PCR and westernblot *** an in vivo model,HIE was induced in postnatal day 7 mice,and UC-MSCs were transplanted via the intraventricular ***-MSC migration was investigated by immunofluorescence,and lesion volumes were measured by TTC *** in injured brain cells was detected by the TUNEL ***-PCR and ELISA were used to detect the expression of inflammatory factors in cells and animal *** Flow cytometry analysis revealed that apoptosis in injured neurons was inhibited by *** RT-PCR and western blot results indicated that coculture inhibited the expression of proapoptotic genes and upregulated expression of antiapoptotic *** the animal model,transplanted UC-MSCs migrated toward the cerebral lesion site and decreased the lesion extent in *** staining showed that the MSC group exhibited significantly reduced numbers of TUNEL-positive ***-PCR and ELISA showed that UC-MSCs inhibited the upregulation of TNF-αand IL-1βin response to hypoxic ischemic *** These results indicate that UC-MSCs exert neuroprotective effects against hypoxic ischemic injury by inhibiting apoptosis,and the mechanism appears to be through alleviating the inflammatory response.

关键词： Apoptosis Hypoxic ischemic encephalopathy Mesenchymal stem cell Transplantation

Albumin resuscitation protects against traumatic/hemorrhagic shock-induced lung apoptosis in rats

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第11期9卷 871-878页

作者： yun ZHANG Zhong-yan LIANG Shao-yang ZHANG fang-fang HUANG Wei WU Yuan GAO Zuo-bing CHEN Department of Emergency Surgery the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China Department of Intensive Care Unit the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China Institute of lnfectious Diseases the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective: To determine the effects of albumin administration on lung injury and apoptosis in traumatic/hemorrhagic shock (T/HS) rats. Methods: Studies were performed on an in vivo model of spontaneously breathing rats with induced T/HS; the rats were subjected to femur fracture, ischemia for 30 min, and reperfusion for 20 min with Ringer's lactate solution (RS) or 5% (w/v) albumin (ALB), and the left lower lobes of the lungs were resected. Results: Albumin administered during reperfusion markedly attenuated injury of the lung and decreased the concentration of lactic acid and the number of in situ TdT-mediated dUTP nick-end labelling (TUNEL)-positive cells. Moreover, immunohistochemistry performed 24 h after reperfusion revealed increases in the level of nuclear factor κB (NF-κB), and phosphorylated p38 mitogen-activated protein kinase (MAPK) in the albumin-untreated group was down-regulated by albumin treatment when compared with the sham rats. Conclusion: Resuscitation with albumin attenuates tissue injury and inhibits T/HS-induced apoptosis in the lung via the p38 MAPK signal transduction pathway that functions to stimulate the activation of NF-κB.

关键词： Traumatic/hemorrhagic shock (T/HS) Mitogen-activated protein kinase (MAPK) Nuclear factor κB (NF-κB) Albumin Apoptosis

Predicting the Mechanical Properties of Polyurethane Elastomers Using Machine Learning

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2023年第3期41卷 422-431,I0009页

作者： fang Ding Lun-yang Liu Ting-Li Liu yun-Qi Li Jun-Peng Li Zhao-Yan Sun State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Department of Polymer Materials and Engineering College of Materials and MetallurgyGuizhou UniversityGuiyang 550025China State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals Sino-Platinum Metals Co.Ltd.Ltdunming 650106China

Bridging the gap between the computation of mechanical properties and the chemical structure of elastomers is a long-standing *** fill the gap,we create a raw dataset and build predictive models for Young’s modulus,tensile strength,and elongation at break of polyurethane elastomers(PUEs).We then construct a benchmark dataset with 50.4%samples remained from the raw dataset which suffers from the intrinsic diversity problem,through a newly proposed recursive data elimination *** coefficients of determination(R^(2)s)from predictions are improved from 0.73-0.78 to 0.85-0.91 based on the raw and the benchmark *** fitting of stress-strain curves using the machine learning model shows a slightly better performance than that for one of the well-performed constitutive models(e.g.,the Khiêm-Itskov model).It confirmed that the black-box machine learning models are feasible to bridge the gap between the mechanical properties of PUEs and multiple factors for their chemical structures,composition,processing,and measurement *** accurate prediction for these curves is still a *** release the raw dataset and the most representative benchmark dataset so far to call for more attention to tackle the longstanding gap problem.

关键词： Mechanical properties Stress-strain curves Polyurethane elastomers Machine learning Benchmark dataset

Influence of Interfacial Enantiomeric Grafting on Melt Rheology and Crystallization of Polylactide/Cellulose Nanocrystals Composites

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2022年第1期40卷 93-106页

作者： Hua-Gao fang Kang-Jie yang Qi-Zheng Xie Xu Chen Sheng-Li Wu yun-Sheng Ding Department of Polymer Science and Engineering School of Chemistry and Chemical EngineeringHefei University of TechnologyHefei 230009China Anhui Province Key Laboratory of Advanced Functional Materials and Devices Hefei 230009China Anhui Institute for Food and Drug Control Hefei230051China

Incorporating the surface-grafted cellulose nanocrystals(CNCs)with enantiomeric polylactide(PLLA or PDLA)is an effective and sustainable way to modify PLLA,but their difference in promoting matrix crystallization is still *** this study,the CNCs with identical content and length of PLLA and PDLA(CNC-g-L and CNC-g-D)were prepared and blended with *** rheological properties of PLLA/CNC-gD are greatly improved,indicating that the stereocomplexation can significantly improve the interfacial strength as compared with the conventional van der Waals force in PLLA/***,the matrix crystallizes at a higher rate in PLLA/CNC-g-L than PLLA/***/CNC-g-L15 reaches its half crystallinity in 8.26 min while a longer period of 13.41 min is required for PLLA/*** observation reveals that the superior crystallization behavior in PLLA/CNC-g-L is originated from its higher nucleation efficiency and faster growth *** formation of low content of sc-PLA at the interface can restrict the diffusion of PLLA but contribute less to generate crystalline nuclei,which synergistically leads to the retarded crystallization kinetics in PLLA/*** the mechanism of different interfacial enantiomeric grafting on the melt rheology and crystallization of PLLA is of great significance for the development of high-performance polylactide materials.

关键词： Cellulose nanocrystal Polylactide nanocomposite Interfacial stereocomplexation Crystallization Rheology