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China Foundry 2023年第1期20卷 49-56页

作者： Tian-yu Liu Kun shi Jun Zhao shi-bing Liu You-wei Zhang Hong-yu Liu Tian-yi Liu Xiao-ming Chen Xin-min Mei Shenyang Research Institute of Foundry Co. Ltd.Shenyang 110022China State Key Laboratory of Light Alloy Casting Technology for High-end Equipment Shenyang 110022China

Hot isostatic pressing parameters are critical to Ti60 high temperature titanium alloy castings which have wide application perspective in *** order to obtain optimal processing parameters,the effects of hot isostatic pressing parameters on defects,composition uniformity,microstructure and mechanical properties of Ti60 cast high temperature titanium alloy were investigated in *** show that increasing temperature and pressure of hot isostatic pressing can reduce defects,especially,the internal defects are substantially eliminated when the temperature exceeds 920℃or the pressure exceeds 125 *** higher temperature and pressure can improve the microstructure ***,the higher pressure can promote the composition *** the temperature increases from 880℃to 960℃,α-laths are *** with increasing pressure,the grain size of prior-βphase,the widths ofα-laths andα-colony are *** tensile strength of Ti60 alloy is 949 MPa,yield strength is 827 MPa,and the elongation is 11%when the hot isostatic pressing parameters are 960℃/125 MPa/2 h,which exhibits the best match between the strength and plasticity.

关键词： hot isostatic pressing processing parameters Ti60 titanium alloy defects composition uniformity microstructure mechanical properties

Stereoselective construction of atropisomers featuring a C-N chiral axis

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Green Synthesis and Catalysis 2022年第2期3卷 117-136页

作者： Yong-Jie Wu Gang Liao bing-Feng shi Center of Chemistry for Frontier Technologies Department of ChemistryZhejiang UniversityHangzhou 310027China Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhou 450001China Department of Chemistry National University of SingaporeSingapore 117543Singapore School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

Atropisomeric C-N compounds belong to an important class of axially chiral ***,whereas the asymmetric synthesis of biaryl atropisomers have been well established,general and efficient strategies to access single enantiomers of C-N atropisomers are still *** recently,innovative methods have been developed,providing new opportunities for the highly stereoselective synthesis of this vital class of ***,we comprehensively summarize the development in this emerging field and give some insights into future *** is placed on the synthetic strategies.

关键词： Atropisomers C-N Chiral axis Asymmetric synthesis Stereoselectivity

Synthesis of C—N Axial Chirality N-Arylindoles via Pd(II)-Catalyzed Free Amine-Directed Atroposelective C—H Olefination

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Chinese Journal of Chemistry 2023年第21期41卷 2788-2792页

作者： Lei Wang Wen-Kui Yuan Zhen-Kai Wang Jun Luo Tao Zhou bing-Feng shi Center of Chemistry for Frontier Technologies Department of ChemistryZhejiang UniversityHangzhouZhejiang310027 China College of Chemistry and Molecular Engineering Zhengzhou UniversityZhengzhouHenan450001 China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan453007 China

Axially chiral N-arylindoles bearing a stereogenic C—N axis are unique important scaffolds in natural products,advance materials,pharmaceuticals and privileged chiral ligands or ***,we report the direct synthesis of C—N axially chiral N-arylindoles through a Pd-catalyzed free amine-directed atroposelective C—H olefination enabled by a spiro phosphoric acid(SPA)ligand.A wide range of enantioenriched N-aromatic amine indoles were obtained in high yields with good enantioselectivities(35 examples,up to 91%yield and up to 96%ee).The chiral products with free amine group offer an effective functional handle for down-stream diversity-oriented synthesis.

关键词： C-N axial chirality Free amine-directed C-H activation Chiral spiro phosphoric acids Palladium Olefination Asymmetric synthesis

Locally and globally uniform approximations for ruin probabilities of a nonstandard bidimensional risk model with subexponential claims

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 98-113页

作者： LIU Zai-ming GENG bing-zhen WANG shi-jie School of Mathematics and Statistics Central South UniversityChangsha 410083China School of Big Data and Statistics Anhui UniversityHefei 230601China

Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair of the claim-inter-arrival times is arbitrarily *** some mild conditions,we achieve a locally uniform approximation of the finite-time ruin probability for all time horizon within a finite *** we further assume that each pair of the claim-inter-arrival times is negative quadrant dependent and the two classes of claims are consistently-varying-tailed,it shows that the above obtained approximation is also globally uniform for all time horizon within an infinite interval.

关键词： bidimensional risk model asymptotic formula subexponential distribution consistently varying tail ruin probability

Composition formula of Al-TMs high-entropy alloys derived by cluster-plus-glue-atoms model and its experimental verification

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China Foundry 2022年第6期19卷 544-550页

作者： Tian-yu Liu Kun shi Jun Zhao shi-bing Liu Hong-yu Liu Bo-liang Liu Xin-min Mei Zhao-sheng Ning Xiao-ming Chen State Key Laboratory of Light Alloy Casting Technology for High-end Equipment Shenyang Research Institute of Foundry Co.Ltd.Shenyang 110022China

High-entropy alloys(HEAs)are based on solid solutions which characterized by chemical short-range ordering(CSRO),but there is no accurate structural tool to address CSRO characteristic,which obstacles precise composition design for *** this study,based on the cluster-plus-glue-atoms model,the composition law of Al-TMs(TMs,transition metals)HEAs with BCC and FCC structures was *** BCC structure,with five elements in equi-atomic ratio,the composition formula of Al-TMs HEAs can be expressed by a cluster formula[Al-M_(14)]Al_(3),and in non equi-atomic ratio can be expressed by[Al-M_(14)]Al,where M is the average atom of the *** in FCC structure,both Al-TMs HEAs with five elements in equiatomic and non equi-atomic ratios can be expressed by a cluster formula[Al-M_(12)]*** confirm the effectiveness of cluster formula for Al-TMs,two alloys were designed,[Al-Ti_(4)V_(3)Nb_(4)Mo_(3)]Mo and[Al-Ti_(3)V_(3)Nb_(4)Mo_(4)]*** show that the[Al-Ti_(3)V_(3)Nb_(4)Mo_(4)]Al alloy has both higher strength and higher plastic deformation at room ***,[Al-Ti_(3)V_(3)Nb_(4)Mo_(4)]Al alloy shows slower soften effect at 800℃,contributed to its higher *** substituting Ta for some of Mo,the strength of[Al-Ti_(3)V_(3)Nb_(4)Mo_(3)Ta]Al at room temperature and high temperature drastically decreases,suggesting that Ta element deteriorates the properties of Al-TMs alloys.

关键词： Al-TMs high-entropy alloys composition design short-range order cluster-plus-glue-atom model

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某车站洞桩法施工工艺及沉降规律研究

建筑机械 2024年第7期 188-192页

作者：史炳峰陈建张文军赵佳明中国港湾工程有限责任公司北京100027 中交第二公路工程局有限公司陕西西安710000

文章以某轨道交通车站为研究对象,运用MIDAS/GTS有限元分析软件建立洞桩法施工的模型,将数值模拟结果与现场监测数据对比,证明了数值模型的可靠性。结果表明,主要地表沉降和水平位移发生在8个小导洞的开挖过程,其次是扣拱下部土体开挖... 详细信息

文章以某轨道交通车站为研究对象,运用MIDAS/GTS有限元分析软件建立洞桩法施工的模型,将数值模拟结果与现场监测数据对比,证明了数值模型的可靠性。结果表明,主要地表沉降和水平位移发生在8个小导洞的开挖过程,其次是扣拱下部土体开挖和初期支护的施工,其他阶段产生的变形较小。

关键词：洞桩法有限元沉降规律开挖顺序

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DNA Methylation and Transcription of HLA-F and Serum Cytokines Relate to Chinese Medicine Syndrome Classification in Patients with Chronic Hepatitis B

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Chinese Journal of Integrative Medicine 2022年第6期28卷 501-508页

作者： HU Xue-qing ZHOU Yuan CHEN Jian LU Yi-yu CHEN Qi-long HU Yi-yang SU shi-bing Research Center for Traditional Chinese Medicine Complexity System Institute of Interdisciplinary Integrative Medicine ResearchShanghai University of Traditional Chinese MedicineShanghai201203China Department of Medical Oncology Shuguang HospitalShanghai University of Traditional Chinese MedicineShanghai201203China Academy of Integrative Medicine Shanghai University of Traditional Chinese MedicineShanghai201203China Department of Vascular Disease Shanghai Traditional Chinese Medicine-Integrated HospitalShanghai University of Traditional Chinese MedicineShanghai201203China Department of Vascular Disease Shanghai Traditional Chinese Medicine-Integrated Institute of Vascular DiseaseShanghai201203China Institute of Liver Disease Shuguang HospitalShanghai University of Traditional Chinese MedicineShanghai201203China

Objective:To explore the molecular bases of Chinese medicine(CM) syndrome classification in chronic hepatitis B(CHB) patients in terms of DNA methylation,transcription and ***:Genome-wide DNA methylation and 48 serum cytokines were detected in CHB patients(DNA methylation:15 cases;serum cytokines:62 cases) with different CM syndromes,including dampness and heat of Gan(Liver) and gallbladder(CHB1,DNA methylation:5 cases,serum cytokines:15 cases),Gan stagnation and Pi(Spleen) deficiency(CHB2,DNA methylation:5 cases,serum cytokines:15 cases),Gan and Shen(Kidney) yin deficiency(CHB3,DNA methylation:5 cases,serum cytokines:16 cases),CHB with hidden symptoms(HS,serum cytokines:16 cases) and healthy controls(DNA methylation:6 cases).DNA methylation of a critical gene was further validated and its mRNA expression was detected on enlarged ***-wide DNA methylation was detected using Human Methylation 450 K Assay and further verified using *** and mRNA expression of gene were evaluated using multiplex biometric enzyme-linked immunosorbent assay(ELISA)-based immunoassay and reverse transcription-quantitative polymerase chain reaction(RT-qPCR),***:Totally 28,667 loci,covering 18,403 genes were differently methylated among CHB1,CHB2 and CHB3(P 0.17).Further validation showed that compared with HS,the hg19 CHR6:29691140 and its closely surrounded 2 CpG loci were demethylated and its mRNA expressions were significantly up-regulated in CHB1(P0.05).Levels of Interleukin(IL)-12 were higher in CHB3 and HS than that in CHB1 and CHB2 groups(P<0.05).Levels of macrophage inflammatory protein(MIP)-1αand MIP-1β were higher in CHB3 than other groups and leukemia inhibrtory factor level was higher in CHB1 and HS than CHB2 and CHB3 groups(P<0.05).IL-12,MIP-1α and MIP-1β concentrations were positively correlated with human leukocyte antigen F(HLA-F)mRNA expression(R

关键词： cytokine chronic hepatitis B DNA methylation human leukocyte antigen F Chinese medicine syndrome

Recent Progress in Fabrication and Structural Design of Thermal Conductive Polymer Composites

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Chinese Journal of Polymer Science 2024年第3期42卷 277-291,I0004页

作者： Yuan-Kai Du Zheng-Xue shi Shan Dong Hui Jin Xue Ke Pei Zhao bing-bing Jiang Feng You Hubei Key Laboratory of Plasma Chemistry and Advanced Materials School of Material Science and EngineeringWuhan Institute of TechnologyWuhan 430205China Key Laboratory of Green Preparation and Application of Functional Materials Ministry of EducationHubei UniversityWuhan 430062China Institute of Molecular Aggregation Science Tianjin UniversityTianjin 300072China

In recent years, the demand direction for electronic equipment has expanded into embedded and miniaturized devices. The heat radiation problem has become one of the most significant factors for hindering the development of electronic devices. Since heat radiation material is one of the important components in electronic devices, the demand for enhancing thermal conductivity is also increasingly urgent. Research on thermal conductive polymer composites has become a major direction for developing functional composites. This work reviewed the recent progress in the fabrication of thermal conductive polymer composites. Five different structures are presented, including the using of single fillers,hybrid fillers, double threshold percolation structure, segregated structure and other complex multiphase structures. Specifically, the preparation of high-performance thermal conductive polymer composites was introduced through the combination of various thermal conductive ***, the development direction of high thermal conductive polymer composites was briefly explored.

关键词： Thermal conductive polymer Hybrid fillers Polymer composite Thermal resistance

Computational technology for nasal cartilage-related clinical research and application

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International Journal of Oral Science 2020年第3期12卷 183-198页

作者： bing shi Hanyao Huang State Key Laboratory of Oral Diseases&National Clinical Research Center for Oral Diseases&Department of Oral Maxillofacial Surgery West China Hospital of StomatologySichuan University610041 ChengduChina

Surgeons need to understand the effects of the nasal cartilage on facial morphology,the function of both soft tissues and hard tissues and nasal function when performing nasal *** nasal cartilage-related surgery,the main goals for clinical research should include clarification of surgical goals,rationalization of surgical methods,precision and personalization of surgical design and preparation and improved convenience of doctor–patient *** technology has become an effective way to achieve these *** in three-dimensional(3D)imaging technology will promote nasal cartilage-related applications,including research on computational modelling technology,computational simulation technology,virtual surgery planning and 3D printing *** technologies are destined to revolutionize nasal surgery *** this review,we summarize the advantages,latest findings and application progress of various computational technologies used in clinical nasal cartilage-related work and *** application prospects of each technique are also discussed.

关键词： nasal clinical application

亚热带同质园不同树种枝、叶氮磷含量及其重吸收特征

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长江流域资源与环境 2024年第5期33卷 993-1003页

作者：赖明玥何樟儒朱鹏杨玉莲李婧李济宏贾世冰李晗张丽谭波徐振锋游成铭长江上游林业生态工程四川省重点实验室长江上游森林资源保育与生态安全国家林业和草原局重点实验室华西雨屏区人工林生态系统研究长期科研基地都江堰灵岩山常绿阔叶林省级长期科研基地四川农业大学林学院四川成都611130 绵阳市安州区自然资源局四川绵阳622651 绵阳师范学院生态安全与保护四川省重点实验室四川绵阳621000

植物氮磷含量及其重吸收特征是揭示林木养分利用策略的有效途径。然而,目前关于不同树种枝、叶氮磷含量及其重吸收特征的研究结果尚不明确。为探究不同树种枝、叶氮磷化学计量及其重吸收效率的变化规律,以亚热带同质园中大叶樟(Cinnamom... 详细信息

植物氮磷含量及其重吸收特征是揭示林木养分利用策略的有效途径。然而,目前关于不同树种枝、叶氮磷含量及其重吸收特征的研究结果尚不明确。为探究不同树种枝、叶氮磷化学计量及其重吸收效率的变化规律,以亚热带同质园中大叶樟(Cinnamomum platyphyllum)、油樟(***)、香樟(***)、香椿(Toona sinensis)、红椿(***)、天竺桂(***)和桤木(Alnus cremastogyne)7种阔叶树种人工林为研究对象,采集其枝、叶(成熟、凋落)样品,测定氮、磷含量,计算重吸收效率。结果表明:(1)桤木成熟(6.35 g/kg)和凋落枝(5.38 g/kg)氮含量显著高于其他树种,但其磷含量则相反,而红椿、香椿、桤木成熟(20.02~23.21 g/kg;1.59~2.75 g/kg)和凋落叶(17.69~21.43 g/kg;1.12~1.95 g/kg)氮、磷含量整体高于其他树种。香樟、油樟成熟叶以及桤木凋落枝、叶氮磷比均显著高于其他树种,且树种枝叶氮磷比均<14,表明该区物种主要受到氮限制。(2)成熟叶氮磷元素的异速指数为0.744,符合氮磷计量关系的2/3法则,但成熟枝和凋落枝、叶则不符合。相较于成熟枝、叶,凋落枝、叶的氮元素变异性更大,但其磷元素则相反。(3)落叶树种桤木、红椿和香椿枝、叶氮重吸收效率均显著低于其他树种(香椿枝除外),但其枝、叶磷重吸收效率整体高于其他树种(桤木枝除外)。(4)叶片氮磷化学计量主要受林分特征和土壤理化性质的共同影响,而枝主要受土壤理化性质的影响。研究结果表明,相较于其他乡土树种,选择桤木和红椿等落叶树种作为人工混交林的改造树种,可能更有利于提升亚热带人工林的质量。

关键词：同质园人工林乡土树种氮磷化学计量养分重吸收效率