期刊文献+
共找到61篇文章
< 1 2 4 >
每页显示 20 50 100
Improved Data Stream Clustering Method: Incorporating KD-Tree for Typicality and Eccentricity-Based Approach
1
作者 Dayu Xu Jiaming Lu +1 位作者 Xuyao zhang hongtao zhang 《Computers, Materials & Continua》 SCIE EI 2024年第2期2557-2573,共17页
Data stream clustering is integral to contemporary big data applications.However,addressing the ongoing influx of data streams efficiently and accurately remains a primary challenge in current research.This paper aims... Data stream clustering is integral to contemporary big data applications.However,addressing the ongoing influx of data streams efficiently and accurately remains a primary challenge in current research.This paper aims to elevate the efficiency and precision of data stream clustering,leveraging the TEDA(Typicality and Eccentricity Data Analysis)algorithm as a foundation,we introduce improvements by integrating a nearest neighbor search algorithm to enhance both the efficiency and accuracy of the algorithm.The original TEDA algorithm,grounded in the concept of“Typicality and Eccentricity Data Analytics”,represents an evolving and recursive method that requires no prior knowledge.While the algorithm autonomously creates and merges clusters as new data arrives,its efficiency is significantly hindered by the need to traverse all existing clusters upon the arrival of further data.This work presents the NS-TEDA(Neighbor Search Based Typicality and Eccentricity Data Analysis)algorithm by incorporating a KD-Tree(K-Dimensional Tree)algorithm integrated with the Scapegoat Tree.Upon arrival,this ensures that new data points interact solely with clusters in very close proximity.This significantly enhances algorithm efficiency while preventing a single data point from joining too many clusters and mitigating the merging of clusters with high overlap to some extent.We apply the NS-TEDA algorithm to several well-known datasets,comparing its performance with other data stream clustering algorithms and the original TEDA algorithm.The results demonstrate that the proposed algorithm achieves higher accuracy,and its runtime exhibits almost linear dependence on the volume of data,making it more suitable for large-scale data stream analysis research. 展开更多
关键词 Data stream clustering TEDA KD-TREE scapegoat tree
下载PDF
Recent advances and key opportunities on in-plane micro-supercapacitors:From functional microdevices to smart integrated microsystems
2
作者 Jieqiong Qin hongtao zhang +4 位作者 Zhi Yang Xiao Wang Pratteek Das Feng Zhou Zhong-Shuai Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期410-431,I0010,共23页
The popularization of portable,implantable and wearable microelectronics has greatly stimulated the rapid development of high-power planar micro-supercapacitors(PMSCs).Particularly,the introduction of new functionalit... The popularization of portable,implantable and wearable microelectronics has greatly stimulated the rapid development of high-power planar micro-supercapacitors(PMSCs).Particularly,the introduction of new functionalities(e.g.,high voltage,flexibility,stretchability,self-healing,electrochromism and photo/thermal response)to PMSCs is essential for building multifunctional PMSCs and their smart selfpowered integrated microsystems.In this review,we summarized the latest advances in PMSCs from various functional microdevices to their smart integrated microsystems.Primarily,the functionalities of PMSCs are characterized by three major factors to emphasize their electrochemical behavior and unique scope of application.These include but are not limited to high-voltage outputs(realized through asymmetric configuration,novel electrolyte and modular integration),mechanical resilience that includes various feats of flexibility or stretchability,and response to stimuli(self-healing,electrochromic,photo-responsive,or thermal-responsive properties).Furthermore,three representative integrated microsystems including energy harvester-PMSC,PMSC-energy consumption,and all-in-one selfpowered microsystems are elaborately overviewed to understand the emerging intelligent interaction models.Finally,the key perspectives,challenges and opportunities of PMSCs for powering smart microelectronics are proposed in brief. 展开更多
关键词 Micro-supercapacitors IN-PLANE Functionalization Integrated microsystem Energy storage
下载PDF
Double-tract reconstruction is superior to esophagogastrostomy in controlling reflux esophagitis and enhancing quality of life after proximal gastrectomy:Results from a prospective randomized controlled clinical trial in China
3
作者 Yinan zhang hongtao zhang +10 位作者 Yan Yan Ke Ji Ziyu Jia Heli Yang Biao Fan Anqiang Wang Xiaojiang Wu Ji zhang Jiafu Ji Xin Ji Zhaode Bu 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2023年第6期645-659,共15页
Objective:The aim of this study was to prospectively compare double-tract reconstruction(DTR)and esophagogastrostomy(EG)after proximal gastrectomy(PG)regarding the incidence of reflux esophagitis,quality of life(QOL),... Objective:The aim of this study was to prospectively compare double-tract reconstruction(DTR)and esophagogastrostomy(EG)after proximal gastrectomy(PG)regarding the incidence of reflux esophagitis,quality of life(QOL),nutritional status and surgical safety.Methods:This study was a randomized controlled trial.Patients eligible for PG were enrolled and randomly assigned to the EG group and DTR group.The characteristics of patients,parameters for surgical safety,incidence of reflux esophagitis,nutrition status and QOL were collected and compared between the two groups.Univariate analysis and multivariate analysis were performed to determine the significant factors affecting the incidence of reflux esophagitis after PG.Results:Thirty-seven patients of the EG group and 36 patients of the DTR group were enrolled.The incidence of reflux esophagitis was significantly lower in the DTR group than in the EG group(8.3%vs.32.4%,P=0.019).The DTR group demonstrated a more favorable QOL than the EG group after PG.The nutritional status was balanced within the EG group and the DTR group.The operation time was longer in the DTR group than in the EG group(191 min vs.221 min,P=0.001),while surgical safety was similar in the two groups.Conclusions:Our research demonstrated that DTR is superior to EG after PG in terms of the incidence of reflux esophagitis and provides a more satisfactory QOL without increasing surgical complications or sacrificing nutritional status. 展开更多
关键词 Double-tract reconstruction proximal gastrectomy quality of life reflux esophagitis
下载PDF
The specificity of ten non-digestible carbohydrates to enhance butyrate-producing bacteria and butyrate production in vitro fermentation
4
作者 Jingjing Xu Ruyue Wang +9 位作者 Weibao Liu Zhongwei Yin Jianrong Wu Xun Yu Wen Wang hongtao zhang Zhitao Li Minjie Gao Li Zhu Xiaobei Zhan 《Food Science and Human Wellness》 SCIE CSCD 2023年第6期2344-2354,共11页
Butyrate and butyrate-producing bacteria are important indicators of gut microbial metabolism in human health.Ten non-digestible carbohydrates(NDCs),including inulin,fructooligosaccharide(FOS),oatsβ-glucans(OGS),oats... Butyrate and butyrate-producing bacteria are important indicators of gut microbial metabolism in human health.Ten non-digestible carbohydrates(NDCs),including inulin,fructooligosaccharide(FOS),oatsβ-glucans(OGS),oatsβ-glucan oligosaccharides(OGOS),Astragalus polysaccharides(APS),Astragalus oligosaccharides(AOS),xanthan gum oligosaccharides(XGOS),gellan gum oligosaccharides(GGOS),curdlan oligosaccharides(COS),and pullulan oligosaccharides(POS)were used to investigate NDC specifi city in modulating butyrate-producing bacteria and butyrate production in 48 h in vitro fermentation studies in combination with fecal inocula from 7 healthy donors and 11 patients with type 2 diabetes(T2D).We observed that the amount of these ten NDCs utilized depended on NDC structure and inter-individual gut microbial differences.XGOS and GGOS fermentations signifi cantly increased butyrate-producing bacteria(especially f_Lachnospiraceae)and butyric acid production.Furthermore,XGOS and GGOS fermentations showed a better ability to consistently modulate gut microbiota composition and metabolic properties between individuals of healthy donors or T2D patients when compared to inulin,FOS,APS,AOS,OGS,OGOS,COS and POS fermentation.This research indicated that xanthan gum and gellan gum oligosaccharides have strong specifi city to enhance butyrate-producing bacteria and butyrate production. 展开更多
关键词 Non-digestible carbohydrates Gut microbiota Butyric acid Butyrate-producing bacteria
下载PDF
非小细胞肺癌免疫治疗生物标志物研究进展 被引量:15
5
作者 江昌 易玲 +2 位作者 高翔 张洪涛 张树才 《中国肺癌杂志》 CAS CSCD 北大核心 2022年第1期46-53,共8页
肺癌是最常见的恶性肿瘤之一,其发病率和死亡率位居所有恶性肿瘤首位。近年来,随着肿瘤免疫学的迅速发展,以细胞毒性T淋巴细胞相关蛋白4(cytotoxic T lymphocyte-associated antigen-4,CTLA-4)、程序性细胞死亡蛋白1(programmed cell de... 肺癌是最常见的恶性肿瘤之一,其发病率和死亡率位居所有恶性肿瘤首位。近年来,随着肿瘤免疫学的迅速发展,以细胞毒性T淋巴细胞相关蛋白4(cytotoxic T lymphocyte-associated antigen-4,CTLA-4)、程序性细胞死亡蛋白1(programmed cell death-1,PD-1)/程序性细胞死亡配体1(programmed cell death ligand 1,PD-L1)为靶点的免疫检查点抑制剂(immune checkpoint inhibitors,ICIs)不断进入临床实践,标志着免疫治疗的重大突破。免疫治疗的出现彻底改变了非小细胞肺癌(non-small cell lung cancer,NSCLC)的治疗现状,但仅有少部分患者能从中持久性获益。因此,如何筛选免疫治疗的获益人群,进一步提高免疫治疗的疗效是当下研究热点。本文聚焦NSCLC免疫治疗相关的生物标记物,并对近年NSCLC免疫治疗生物标志物研究现状和进展进行综述,为免疫治疗的临床实践提供参考。 展开更多
关键词 非小细胞肺癌 免疫治疗 生物标志物 PD-L1 TMB
下载PDF
Optimization of rice wine fermentation process based on the simultaneous saccharification and fermentation kinetic model 被引量:10
6
作者 Dengfeng Liu hongtao zhang +1 位作者 Chi-Chung Lin Baoguo Xu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第10期1406-1412,共7页
Chinese rice wine making is a typical simultaneous saccharification and fermentation(SSF) process.During the fermentation process,temperature is one of the key parameters which decide the quality of Chinese rice wine.... Chinese rice wine making is a typical simultaneous saccharification and fermentation(SSF) process.During the fermentation process,temperature is one of the key parameters which decide the quality of Chinese rice wine.To optimize the SSF process for Chinese rice wine brewing,the effects of temperature on the kinetic parameters of yeast growth and ethanol production at various temperatures were determined in batch cultures using a mathematical model.The kinetic parameters as a function of temperature were evaluated using the software Origin8.0.Combing these functions with the mathematical model,an appropriate form of the model equations for the SSF considering the effects of temperature were developed.The kinetic parameters were found to fit the experimental data satisfactorily with the developed temperature-dependent model.The temperature profile for maximizing the ethanol production for rice wine fermentation was determined by genetic algorithm.The optimum temperature profile began at a low temperature of 26 °C up to 30 h.The operating temperature increased rapidly to 31.9 °C,and then decreased slowly to 18 °C at 65 h.Thereafter,the temperature was maintained at18 °C until the end of fermentation.A maximum ethanol production of 89.3 g·L^(-1)was attained.Conceivably,our model would facilitate the improvement of Chinese rice wine production at the industrial scale. 展开更多
关键词 中国米饭酒 控制的温度 同时的 saccharification 和发酵 最佳的温度侧面
下载PDF
Characteristics of vascular lesions in patients with posterior circulation infarction according to age and region of infarct 被引量:5
7
作者 Daopei zhang Shuling zhang +1 位作者 hongtao zhang Yuming Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第32期2536-2541,共6页
Patients with posterior circulation infarction underwent CT angiography and magnetic resonance angiography. Intracranial and extracranial vasculopathy was evaluated according to age group and location of stroke. Patie... Patients with posterior circulation infarction underwent CT angiography and magnetic resonance angiography. Intracranial and extracranial vasculopathy was evaluated according to age group and location of stroke. Patients aged > 60 years and < 60 years had similar rates of vertebral artery dominance and vertebrobasilar artery developmental or origin anomalies. Vertebrobasilar artery stenosis or occlusion and tortuosity occurred more frequently in patients aged > 60 years than < 60 years. The rates of vertebrobasilar artery anomalies and tortuosity were high in patients with posterior circulation infarction. Vertebrobasilar artery tortuosity occurred more frequently in patients aged > 60 years, whereas vertebrobasilar artery developmental anomalies occurred with similar frequency in patients aged < 60 years and > 60 years. Patients with infarction of the brainstem or cerebellum were more likely to have vertebral artery stenosis or occlusion, basilar artery stenosis or occlusion, vertebral artery dominance or tortuosity, and basilar artery tortuosity, and patients with infarction of the thalamus, medial temporal, or occipital lobes were more likely to have stenosis or occlusion of the vertebral or basilar arteries. Vertebrobasilar artery tortuosity, vertebral artery dominance (hypoplasia), and congenital variations of the vertebrobasilar system may lead to posterior circulation infarction at different locations in different age groups. 展开更多
关键词 血管病变 年龄组 患者 循环 基底动脉 动脉狭窄 发育异常 特征
下载PDF
Comparison of rumen bacteria distribution in original rumen digesta, rumen liquid and solid fractions in lactating Holstein cows 被引量:4
8
作者 Shoukun Ji hongtao zhang +6 位作者 Hui Yan Arash Azarfar Haitao Shi Gibson Alugongo Shengli Li Zhijun Cao Yajing Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第3期636-642,共7页
Background: Original rumen digesta, rumen liquid and solid fractions have been frequently used to assess the rumen bacterial community. However, bacterial profiles in rumen original digesta, liquid and solid fractions... Background: Original rumen digesta, rumen liquid and solid fractions have been frequently used to assess the rumen bacterial community. However, bacterial profiles in rumen original digesta, liquid and solid fractions vary from each other and need to be better established.Methods: To compare bacterial profiles in each fraction, samples of rumen digesta from six cows fed either a high fiber diet(HFD) or a high energy diet(HED) were collected via rumen fistulas. Rumen digesta was then squeezed through four layers of cheesecloth to separate liquid and solid fractions. The bacterial profiles of rumen original digesta, liquid and solid fractions were analyzed with High-throughput sequencing technique.Results: Rumen bacterial diversity was mainly affected by diet and individual cow(P > 0.05) rather than rumen fraction. Bias distributed bacteria were observed in solid and liquid fractions of rumen content using Venn diagram and LEf Se analysis. Fifteen out of 16 detected biomarkers(using LEf Se analysis) were found in liquid fraction, and these 15 biomarkers contributed the most to the bacterial differences among rumen content fractions.Conclusions: Similar results were found when using samples of original rumen digesta, rumen liquid or solid fractions to assess diversity of rumen bacteria; however, more attention should be draw onto bias distributed bacteria in different ruminal fractions, especially when liquid fraction has been used as a representative sample for rumen bacterial study. 展开更多
关键词 瘤胃细菌 液体 组分 固体 奶牛 细菌多样性 生物标志物 瘤胃内容物
下载PDF
翻转课堂在ESP教学中的应用探析 被引量:1
9
作者 张洪涛 《西北成人教育学院学报》 2019年第3期81-84,共4页
在高等教育国际化和信息技术飞速发展的形势下,大学英语教育应该顺应时代发展做出必要的改革。ESP教学在经过二十年的发展之后,被证明可以作为大学英语教学有益的尝试。翻转课堂也为大学英语教学提供了突破传统的新模式。对比分析ESP教... 在高等教育国际化和信息技术飞速发展的形势下,大学英语教育应该顺应时代发展做出必要的改革。ESP教学在经过二十年的发展之后,被证明可以作为大学英语教学有益的尝试。翻转课堂也为大学英语教学提供了突破传统的新模式。对比分析ESP教学和翻转课堂在教学理念上的共通之处的基础上,探究翻转课堂在ESP教学中的模式构建与应用,以及翻转课堂如何助力ESP教学得到更好的实现。 展开更多
关键词 翻转课堂 ESP教学 探析
下载PDF
Functional recovery and microenvironmental alterations in a rat model of spinal cord injury following human umbilical cord blood-derived mesenchymal stem cells transplantation 被引量:3
10
作者 hongtao zhang Huilin Yang +1 位作者 Huanxiang zhang Jing Qu 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第3期165-170,共6页
BACKGROUND: Transplantation of human umbilical cord blood-derived mesenchymal stem cells (MSCs) has been shown to benefit spinal cord injury (SCI) repair. However, mechanisms of microenvironmental regulation during di... BACKGROUND: Transplantation of human umbilical cord blood-derived mesenchymal stem cells (MSCs) has been shown to benefit spinal cord injury (SCI) repair. However, mechanisms of microenvironmental regulation during differentiation of transplanted MSCs remain poorly understood. OBJECTIVE: To observe changes in nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and interleukin-8 (IL-8) expression following transplantation of human umbilical cord-derived MSCs, and to explore the association between microenvironment and neural functional recovery following MSCs transplantation. DESIGN, TIME AND SETTING: A randomized, controlled, animal experiment was performed at the Department of Orthopedics, First Affiliated Hospital of Soochow University from April 2005 to March 2007. MATERIALS: Human cord blood samples were provided by the Department of Gynecology and Obstetrics, First Affiliated Hospital of Soochow University. Written informed consent was obtained. METHODS: A total of 62 Wister rats were randomly assigned to control (n = 18), model (n = 22, SCI + PBS), and transplantation (n = 22, SCI + MSCs) groups. The rat SCI model was established using the weight compression method. MSCs were isolated from human umbilical cord blood and cultured in vitro for several passages. 5-bromodeoxyuridine (BrdU)-labeled MSCs (24 hours before injection) were intravascularly transplanted. MAIN OUTCOME MEASURES: The rats were evaluated using the Basso, Beattie and Bresnahan (BBB) locomotor score and inclined plane tests. Transplanted cells were analyzed following immunohistochemistry. Enzyme-linked immunosorbant assay was performed to determine NGF, BDNF, and IL-8 levels prior to and after cell transplantation. RESULTS: A large number of BrdU-positive MSCs were observed in the SCI region of the transplantation group, and MSCs were evenly distributed in injured spinal cord tissue 1 week after transplantation. BBB score and inclined plane test results revealed significant functional improvement in the transplantation group compared to the model group (P < 0.05), which was maintained for 2-3 weeks. Compared to the model group, NGF and BDNF levels were significantly increased in the injured region following MSCs transplantation at 3 weeks (P < 0.05), but IL-8 levels remained unchanged (P > 0.05). CONCLUSION: MSCs transplantation increased NGF and BDNF expression in injured spinal cord tissue. MSCs could promote neurological function recovery in SCI rats by upregulating NGF expression and improving regional microenvironments. 展开更多
关键词 human umbilical cord blood-derived mesenchymal stem cells nerve growth factor brain-derived neurotrophic factor INTERLEUKIN-8 spinal cord injury neural stem cells neural regeneration
下载PDF
低碰撞能3.03~17.97 meV内F+HD→DF+H的反应微分截面
11
作者 王黑龙 李煜 +3 位作者 焦志润 张宏涛 肖春雷 杨学明 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第6期925-931,I0005,共8页
基于氢原子里德堡态飞行时间谱探测方法及多通道探测的优势,利用交叉分子束实验装置系统地研究了低碰撞能3.03~17.97 meV内的F+HD→DF+H反应.实验中清楚地观测到来自波恩-奥本海默近似禁阻的反应F^(*)(^(2)P_(1/2))+HD→DF+H和波恩-奥... 基于氢原子里德堡态飞行时间谱探测方法及多通道探测的优势,利用交叉分子束实验装置系统地研究了低碰撞能3.03~17.97 meV内的F+HD→DF+H反应.实验中清楚地观测到来自波恩-奥本海默近似禁阻的反应F^(*)(^(2)P_(1/2))+HD→DF+H和波恩-奥本海默近似允许的反应F(^(2)P_(3/2))+HD→DF+H的贡献.在后向散射方向上,波恩-奥本海默近似禁阻的反应F^(*)(^(2)P_(1/2))+HD的贡献远远大于波恩-奥本海默近似允许的反应F(^(2)P_(3/2))+HD,表明非绝热效应在低碰撞能下F+HD→DF+H中扮演着重要角色.并且,后向散射信号随着碰撞能的降低而单调降低,未出现反应共振的特征.实验中还获得了低碰撞能3.03~17.97 meV内波恩-奥本海默近似禁阻的和波恩-奥本海默近似允许的反应微分截面,其中最出乎意料的现象是:随着碰撞能的降低,产物的角分布由后向散射逐渐转变为侧向散射,这可能是在低碰撞下存在的某种未知反应机理引起的. 展开更多
关键词 钙释放激活的钙通道 反应动力学 交叉分子束实验 非绝热效应 低碰撞能
下载PDF
Conversion of syngas to higher alcohols over Cu-Fe-Zr catalysts induced by ethanol 被引量:3
12
作者 hongtao zhang Xiaomei Yang +2 位作者 Lipeng Zhou Yunlai Su Zhongmin Liu 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2009年第3期337-340,共4页
Ethanol induced method was applied to prepare Cu-Fe-Zr catalysts for conversion of syngas to higher alcohols.The catalytic performance of the catalysts induced by ethanol was superior to that of the catalyst prepared ... Ethanol induced method was applied to prepare Cu-Fe-Zr catalysts for conversion of syngas to higher alcohols.The catalytic performance of the catalysts induced by ethanol was superior to that of the catalyst prepared by the conventional precipitation method.Among various procedures for ethanol induced method,it was found that incorporation of ethanol in the precipitation process was the better.After incorporation of ethanol,the crystal size of CuO decreased and the reduction of copper species became easier.The better activity of Cu-Fe-Zr catalysts prepared by ethanol induced procedures was probably caused by the higher dispersion of Cu species. 展开更多
关键词 铁锆催化剂 诱导方法 氧化铜 合成气 乙醇 转化 低碳醇 催化性能
下载PDF
PLASTIC LIMIT ANALYSIS OF DUCTILE COMPOSITE STRUCTURES FROM MICRO-TO MACRO-MECHANICAL ANALYSIS 被引量:3
13
作者 hongtao zhang Yinghua Liu Binge Xu 《Acta Mechanica Solida Sinica》 SCIE EI 2009年第1期73-84,共12页
The load-bearing capacity of ductile composite structures comprised of periodic composites is studied by a combined micro/macromechanical approach. Firstly,on the microscopic level,a representative volume element (RVE... The load-bearing capacity of ductile composite structures comprised of periodic composites is studied by a combined micro/macromechanical approach. Firstly,on the microscopic level,a representative volume element (RVE) is selected to reflect the microstructures of the composite materials and the constituents are assumed to be elastic perfectly-plastic. Based on the homogenization theory and the static limit theorem,an optimization formulation to directly calculate the macroscopic strength domain of the RVE is obtained. The finite element modeling of the static limit analysis is formulated as a nonlinear mathematical programming and solved by the sequential quadratic programming method,where the temperature parameter method is used to construct the self-stress field. Secondly,Hill's yield criterion is adopted to connect the micromechanical and macromechanical analyses. And the limit loads of composite structures are worked out on the macroscopic scale. Finally,some examples and comparisons are shown. 展开更多
关键词 复合材料结构 宏观力学分析 塑性极限分析 微观结构 韧性 非线性数学规划 连续二次规划法 均匀化理论
下载PDF
碰撞能44~164 cm^(-1)范围内单量子态转动激发对F+D_(2)反应的影响
14
作者 焦志润 王黑龙 +3 位作者 李煜 张宏涛 肖春雷 杨学明 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第2期263-269,I0001,共8页
当碰撞能很低,尤其是远低于反应势垒的时候,反应通常经过量子隧穿来进行.目前,还没有明确的物理图像来描述反应物的转动激发对这类反应过程的影响.本文基于里德堡态D原子飞行时间谱探测方法,利用多通道探测器交叉分子束装置研究了碰撞能... 当碰撞能很低,尤其是远低于反应势垒的时候,反应通常经过量子隧穿来进行.目前,还没有明确的物理图像来描述反应物的转动激发对这类反应过程的影响.本文基于里德堡态D原子飞行时间谱探测方法,利用多通道探测器交叉分子束装置研究了碰撞能44 cm^(-1)~164 cm^(-1)下反应F+D_(2)(v=0,j=0,1)→DF(v’)+D的动力学过程,并得到了振动态分辨的微分截面.在可资用能相等时,通过调控反应的平动能,研究了D_(2)转动激发对于反应的影响,发现反应物的转动比平动更有利于反应的进行.D_(2)的转动激发导致产物DF的角分布和量子态分布发生显著变化.本工作进一步加深转动激发对于反应的影响的理解,尤其是在反应能量远低于反应势垒的情况下. 展开更多
关键词 交叉分子束实验 微分截面 转动激发
下载PDF
FOXP3 and Its Cofactors as Targets of Immunotherapies 被引量:2
15
作者 Yasuhiro Nagai Lian Lam +1 位作者 Mark I. Greene hongtao zhang 《Engineering》 SCIE EI 2019年第1期115-121,共7页
Forkhead box P3 (FOXP3) is a “master regulator” of regulatory T cells (Tregs), which are a subset of T cells that can suppress the antigen-specific immune reaction and that play important roles in host tolerance and... Forkhead box P3 (FOXP3) is a “master regulator” of regulatory T cells (Tregs), which are a subset of T cells that can suppress the antigen-specific immune reaction and that play important roles in host tolerance and immune homeostasis. It is well known that FOXP3 forms complexes with several proteins and can be regulated by various post-translational modifications (PTMs) such as acetylation, phosphorylation, ubiquitination, and methylation. As a consequence, the PTMs change the stability of FOXP3 and its capability to regulate gene expression, and eventually affect Treg activity. Although FOXP3 per se is not an ideal drug target, deacetylases, acetyltransferases, kinases, and other enzymes that regulate the PTMs of FOXP3 are potential targets to modulate FOXP3 and Treg activity. However, FOXP3 is not the only substrate for most of these enzymes;thus, unwanted ‘‘on target/off FOXP3” side effects must be considered when inhibitors to these enzymes are used. In this review, we summarize recent progress in the study of FOXP3 cofactors and PTM proteins, and potential clinical applications in autoimmunity and cancer immunity. 展开更多
关键词 Treg FORKHEAD box P3 (FOXP3) POST-TRANSLATIONAL modification AUTOIMMUNE Cancer
下载PDF
Preparation of Spherical FePO4 by Chemical Co-precipitation Combined with Spray-Drying 被引量:3
16
作者 Leping Dang hongtao zhang +1 位作者 Xin Xu Xiaojun Lang 《Transactions of Tianjin University》 EI CAS 2020年第1期57-66,共10页
Well-shaped spherical agglomerates of FePO4 particles were prepared by a novel method:chemical co-precipitation combined with spray-drying.Tap density analysis,Brunauer-Emmett-Teller analysis,characterizations of X-ra... Well-shaped spherical agglomerates of FePO4 particles were prepared by a novel method:chemical co-precipitation combined with spray-drying.Tap density analysis,Brunauer-Emmett-Teller analysis,characterizations of X-ray diffraction,scanning electron microscopy,and transmission electron microscopy confirmed that the micron-sized spherical agglomerates with high specific surface area and high tap density were composed of the uniform nano-sized particles.The effects of pH and reaction time on the morphology of the FePO4 particles were investigated by experimental and theoretical analyses.The analyses revealed that amorphous FePO4 was responsible for forming a well-shaped spherical agglomerate,and the ideal spherical particles were obtained at pH 3.The reaction time also played a significant role in controlling the size and surface morphology of the FePO4 particles,and smooth spherical FePO4 particles were obtained at a reaction time of 6 h.By this novel method,poly-porous spherical iron phosphate particles were prepared,which can be used with high efficiency in some special fields,especially as a precursor for synthesizing LiFePO4 and catalysts. 展开更多
关键词 FEPO4 Spherical agglomerate SPRAY-DRYING pH Reaction time
下载PDF
Rock borehole shear tests in dam foundation of Xiangjiaba hydropower station 被引量:2
17
作者 Yufei Zhao Xiaogang Wang +3 位作者 Xiaohui zhang Zhixin Jia Xiangxi Zeng hongtao zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2012年第4期360-366,共7页
Xiangjiaba hydropower station is one of the cascade power stations on the Jinsha River, China. Due to the complicated geological conditions of its dam foundation, evaluating the rock mass quality and determining the m... Xiangjiaba hydropower station is one of the cascade power stations on the Jinsha River, China. Due to the complicated geological conditions of its dam foundation, evaluating the rock mass quality and determining the mechanical parameters of rock masses are very important issues. To address these issues, several groups of rock borehole shear tests (RBSTs) were conducted on the black mudstone in the dam foundation of Xiangjiaba hydropower station in the second construction phase. Forty three groups of shear strengths of black mudstone samples were obtained from RBSTs, and the shear strength parameters (c and f ) were calculated using the least squares method. In addition, the limitations and merits of RBST employed in the Xiangjiaba hydropower station were discussed. Test results indicate that the shear strength parameters obtained from RBST have a good correlation with the results from sound wave test in borehole. It is believed that RBST has a good adaptability and applicability in geotechnical engineering. 展开更多
关键词 向家坝水电站 岩石钻孔 剪切试验 坝基 岩体质量评价 抗剪强度参数 最小二乘法 地质条件
下载PDF
Recent progress in the machine learning-assisted rational design of alloys 被引量:2
18
作者 Huadong Fu hongtao zhang +2 位作者 Changsheng Wang Wei Yong Jianxin Xie 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第4期635-644,共10页
Alloys designed with the traditional trial and error method have encountered several problems,such as long trial cycles and high costs.The rapid development of big data and artificial intelligence provides a new path ... Alloys designed with the traditional trial and error method have encountered several problems,such as long trial cycles and high costs.The rapid development of big data and artificial intelligence provides a new path for the efficient development of metallic materials,that is,machine learning-assisted design.In this paper,the basic strategy for the machine learning-assisted rational design of alloys was introduced.Research progress in the property-oriented reversal design of alloy composition,the screening design of alloy composition based on models established using element physical and chemical features or microstructure factors,and the optimal design of alloy composition and process parameters based on iterative feedback optimization was reviewed.Results showed the great advantages of machine learning,including high efficiency and low cost.Future development trends for the machine learning-assisted rational design of alloys were also discussed.Interpretable modeling,integrated modeling,high-throughput combination,multi-objective optimization,and innovative platform building were suggested as fields of great interest. 展开更多
关键词 machine learning data mining rational design ALLOYS
下载PDF
Rapid design of secondary deformation-aging parameters for ultra-low Co content Cu-Ni-Co-Si-X alloy via Bayesian optimization machine learning 被引量:1
19
作者 hongtao zhang Huadong Fu +1 位作者 Yuheng Shen Jianxin Xie 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第6期1197-1205,共9页
It is difficult to rapidly design the process parameters of copper alloys by using the traditional trial-and-error method and simultaneously improve the conflicting mechanical and electrical properties.The purpose of ... It is difficult to rapidly design the process parameters of copper alloys by using the traditional trial-and-error method and simultaneously improve the conflicting mechanical and electrical properties.The purpose of this work is to develop a new type of Cu-Ni-Co-Si alloy saving scarce and expensive Co element,in which the Co content is less than half of the lower limit in ASTM standard C70350 alloy,while the properties are as the same level as C70350 alloy.Here we adopted a strategy combining Bayesian optimization machine learning and experimental iteration and quickly designed the secondary deformation-aging parameters(cold rolling deformation 90%,aging temperature 450℃,and aging time 1.25 h)of the new copper alloy with only 32 experiments(27 basic sample data acquisition experiments and 5 iteration experiments),which broke through the barrier of low efficiency and high cost of trial-and-error design of deformation-aging parameters in precipitation strengthened copper alloy.The experimental hardness,tensile strength,and electrical conductivity of the new copper alloy are HV(285±4),(872±3)MPa,and(44.2±0.7)%IACS(international annealed copper standard),reaching the property level of the commercial lead frame C70350 alloy.This work provides a new idea for the rapid design of material process parameters and the simultaneous improvement of mechanical and electrical properties. 展开更多
关键词 copper alloy process design machine learning Bayesian optimization utility function
下载PDF
Research and Application of CO<sub>2</sub>Flooding Enhanced Oil Recovery in Low Permeability Oilfield 被引量:2
20
作者 Qigui Cheng Zhongxin Li +1 位作者 Guangshe Zhu hongtao zhang 《Open Journal of Geology》 2017年第9期1435-1440,共6页
This paper discusses the new progress and field application of CO2 flooding in low permeability reservoirs enhanced oil recovery. The study shows that CO2 flooding can improve the oil recovery rate of low permeability... This paper discusses the new progress and field application of CO2 flooding in low permeability reservoirs enhanced oil recovery. The study shows that CO2 flooding can improve the oil recovery rate of low permeability oilfield by more than 10%. The practice shows that the liquid CO2 injection in low permeability reservoir is easier than water injection, and the reservoir generally has better CO2 storage. 展开更多
关键词 Low PERMEABILITY OIL Field CO2 FLOODING Enhanced OIL RECOVERY Storage
下载PDF
上一页 1 2 4 下一页 到第
使用帮助 返回顶部