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给水厂典型工艺碳排放特征与影响因素

环境科学 2024年第1期45卷 123-130页

作者：张翔宇胡建坤马凯高欣慰魏月华韩宏大李克勋天津水务集团有限公司天津300042 南开大学环境科学与工程学院天津300350 天津市自来水集团有限公司天津300040 天津市自来水集团有限公司凌庄水厂天津300381

基于实际运行工况和数据监测基础,对天津市给水厂典型工艺的碳排放特征进行研究.给水厂总碳排放强度(以CO_(2)-eq计)为0.254 kg·m^(-3),其中电耗和药耗碳排放占比分别为81.76%和9.15%.给水厂的关键电耗碳排放环节为送水泵房、超滤膜工... 详细信息

基于实际运行工况和数据监测基础,对天津市给水厂典型工艺的碳排放特征进行研究.给水厂总碳排放强度(以CO_(2)-eq计)为0.254 kg·m^(-3),其中电耗和药耗碳排放占比分别为81.76%和9.15%.给水厂的关键电耗碳排放环节为送水泵房、超滤膜工艺和进水泵房,分别占总电耗碳排放的50.99%~73.51%、17.64%~20.70%和17.97%~22.40%.次氯酸钠对药耗碳排放的贡献率为89.12%~90.30%,其余依次为三氯化铁、聚合氯化铝和硫酸铵.传统净水工艺单元的电耗碳排放强度依次为:进水泵房>快滤池>沉淀池,在深度处理工艺线中依次为:进水泵房>超滤膜>机械混凝>澄清池.快滤池工艺线和超滤膜工艺线的碳排放强度分别为0.0709 kg·m^(-3)和0.1090 kg·m^(-3).超滤膜工艺能节约23%的药剂用量,而电耗碳排放是传统处理工艺的2倍.对关键环节的碳排放影响因素分析结果表明,浊度、pH、氨氮和温度等原水水质参数与次氯酸钠碳排放强度显著相关;出厂水压力、日送水量与送水泵房碳排放强度呈显著的线性回归关系,相关水质和水压调控措施可以有效减少给水厂碳排放.

关键词：碳排放给水厂超滤膜快滤池电耗药耗

Phase-field Modeling of the Influence of Elastic Field on the Nucleation and Microstructure Evolution in Precipitation

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Chinese Journal of Aeronautics 2007年第2期20卷 107-110页

作者： zhang yu-xiang WANG Jin-cheng YANG yu-juan YANG Gen-cang ZHOU Yao-he State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi＇an 710072 China

A phase-field method was employed to study the influence of elastic field on the nucleation and microstructure evolution. Two kinds of nucleation process were considered： one using fixed nucleation probability and the other calculated from the classical nucleation theory. In the latter case, the simulated results show that the anisotropic elastic strain field yields significant effects on the behavior of nucleation. With a large lattice misfit between the matrixes and the precipitates, the nucleation process does not appear fully random but displays some spatial correlation and has a preference for the elastic soft direction. However, with a small lattice misfit, this bias does not look quite clear. On the contrary, in the case of fixed nucleation probability, the elastic field has no influence on the nucleation process. The lattice mismatch also exerts influences on the microstructure morphology： with lattice mismatch becoming larger, the microstructure proves to align along the elastic soft direction.

关键词： elastic field nucleation phase-field method precipitation

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RNA可变剪接在药物成瘾中的作用研究进展

中国药物依赖性杂志 2024年第2期33卷 102-108页

作者：陈振楠高靖麒于东玉杨潇宇张玉向阎春霞西安交通大学法医学院西安710061 国家卫生健康委员会法医学重点实验室西安交通大学西安710061 西安交通大学西部科技创新港生物证据研究院西安712000

药物成瘾是一种慢性复发性脑疾病,受遗传和环境等因素的共同影响。基因在RNA水平的可变剪接广泛存在于机体生长发育和疾病发生发展过程中,也是药物成瘾的重要调控机制之一。本文综述了可变剪接调控机制及在药物成瘾中作用的研究进展,以... 详细信息

药物成瘾是一种慢性复发性脑疾病,受遗传和环境等因素的共同影响。基因在RNA水平的可变剪接广泛存在于机体生长发育和疾病发生发展过程中,也是药物成瘾的重要调控机制之一。本文综述了可变剪接调控机制及在药物成瘾中作用的研究进展,以期从RNA可变剪接角度挖掘药物成瘾的分子机制和新的治疗靶点。

关键词：可变剪接药物成瘾脑神经系统疾病 mRNA剪接

Reduction of unactivated alkyl chlorides enabled by light-induced single electron transfer

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Science China Chemistry 2024年第2期67卷 471-481页

作者： Lei Dai Zhao-Fei zhang xiang-yu Chen School of Chemical Sciences University of the Chinese Academy of SciencesBeijing100049China Institute of Chemistry Chinese Academy of SciencesBeijing100190China Binzhou Institute of Technology Weiqiao-UCAS Science and Technology ParkBinzhou256606China

Alkyl chlorides are abundant and easily accessible starting ***,due to the high reduction potentials associated with unactivated alkyl chlorides,achieving their single electron reduction remains a persistent *** challenge has spurred the exploration of efficient activation methods to overcome this *** recent years,photocatalysis has emerged as a mild and potent tool for the single electron reduction of unactivated alkyl chlorides,opening up new possibilities in this *** the rapid advancements in this area,a comprehensive review that provides a conceptual understanding of this emerging field,with a specific focus on reaction design and catalytic mechanisms,would be timely and highly ***,we present an overview of various synthetic techniques for photoinduced single electron reduction of unactivated alkyl ***,we also discuss the limitations of the present methods and future directions that lie ahead in this field.

关键词： photocatalysis unactivated alkyl chlorides single electron transfer radical reactions

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基于比例风险模型的飞机部件剩余寿命预测

计算机工程与设计 2024年第4期45卷 1109-1116页

作者：何浪鲁亮陆锦鹤范圣娴赵立新张宇翔中国民航大学计算机科学与技术学院天津300300 北京飞机维修工程有限公司附件/起落架大修产品事业部北京100621

为准确预测飞机部件的剩余寿命,在对某航空公司最近4年的163架波音B737 NG型号飞机的维修数据进行分析的基础上,提出基于比例风险模型的飞机部件剩余寿命预测方法。通过估计部件装拆间隔飞行时间对应的寿命分布,计算部件在当前时刻对应... 详细信息

为准确预测飞机部件的剩余寿命,在对某航空公司最近4年的163架波音B737 NG型号飞机的维修数据进行分析的基础上,提出基于比例风险模型的飞机部件剩余寿命预测方法。通过估计部件装拆间隔飞行时间对应的寿命分布,计算部件在当前时刻对应的可靠度;对部件的维修数据进行分析,筛选出影响部件寿命的主要因素;据此预测部件的剩余寿命。通过实例分析,部件的累计飞行时间、飞机的机龄以及飞机的运行环境等均为影响部件寿命的重要因素。实验结果表明,基于比例风险模型的预测结果较其它预测模型在3个评价指标上均取得了最好效果。

关键词：比例风险模型可靠性分析特征选择比例风险假设检验剩余寿命飞机部件维修预测

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煤矿取用水智慧水务管理系统建设实践

水电能源科学 2024年第5期42卷 76-79页

作者：贾一飞张翔宇李恩宽李强坤白乐黄河水利科学研究院河南郑州450003

为提高煤矿的取用水效率,建立了煤矿取用水智慧水务管理系统,该系统采用MLP神经网络模型,通过深度学习不同煤矿各用水环节的用水指标,并与相关用水定额进行综合对比,确定适合于系统应用煤矿各环节的合理用水区间,通过实时计算分析用水数... 详细信息

为提高煤矿的取用水效率,建立了煤矿取用水智慧水务管理系统,该系统采用MLP神经网络模型,通过深度学习不同煤矿各用水环节的用水指标,并与相关用水定额进行综合对比,确定适合于系统应用煤矿各环节的合理用水区间,通过实时计算分析用水数据,及时预报预警不合理的用水环节,并将该系统应用于内蒙古鄂尔多斯市某煤矿中。结果表明,系统应用后该煤矿年取水量由117.75×10~4m~3降至86.87×10~4m~3,节水率达到26.23%,节水效果明显。可为后续煤矿类智慧水务管理系统的建设提供参考。

关键词：煤矿智慧水务信息化水资源管理系统设计

Protein tyrosine phosphatase 1B inhibitory activities of ursane-type triterpenes from Chinese raspberry, fruits of Rubus chingii

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Chinese Journal of Natural Medicines 2019年第1期17卷 15-21页

作者： zhang xiang-yu LI Wei WANG Jian LI Ning CHENG Mao-Sheng KOIKE Kazuo Key Laboratory of Structure-Based Drug Design&Discovery Ministry of EducationShenyang Pharmaceutical University School of Pharmaceutical Engineering Shenyang Pharmaceutical University Faculty of Pharmaceutical Sciences Toho University

Protein tyrosine phosphatase 1 B(PTP1 B) has led to an intense interest in developing its inhibitors as anti-diabetes, anti-obesity and anti-cancer agents. The fruits of Rubus chingii(Chinese raspberry) were used as a kind of dietary traditional Chinese medicine. The methanolic extract of R. chingii fruits exhibited significant PTP1 B inhibitory activity. Further bioactivity-guided fractionation resulted in the isolation of three PTP1 B inhibitory ursane-type triterpenes: ursolic acid(1), 2-oxopomolic acid(2), and 2α, 19α-dihydroxy-3-oxo-urs-12-en-28-oic acid(3). Kinetics analyses revealed that 1 was a non-competitive PTP1 B inhibitor, and 2 and 3 were mixed type PTP1 B inhibitors. Compounds 1-3 and structurally related triterpenes(4-8) were further analyzed the structure-activity relationship, and were evaluated the inhibitory selectivity against four homologous protein tyrosine phosphatases(TCPTP, VHR, SHP-1 and SHP-2). Molecular docking simulations were also carried out, and the result indicated that 1, 3-acetoxyurs-12-ene-28-oic acid(5), and pomolic acid-3β-acetate(6) bound at the allosteric site including α3, α6, and α7 helix of PTP1 B.

关键词： Protein tyrosine phosphatase 1B Raspberry Rubus chingii Triterpene Ursane

Bile acids,gut microbiota,and therapeutic insights in hepatocellular carcinoma

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Cancer Biology & Medicine 2024年第2期21卷 144-162页

作者： Yang Song Harry CH Lau xiang zhang Jun yu Institute of Digestive Disease and Department of Medicine and Therapeutics State Key Laboratory of Digestive DiseaseLi Ka Shing Institute of Health SciencesCUHK Shenzhen Research InstituteThe Chinese University of Hong KongHong KongChina Department of Gastroenterology Zhongshan Hospital Xiamen UniversityXiamen 361004China

Hepatocellular carcinoma(HCC)is a prevalent and aggressive liver *** interplay between bile acids(BAs)and the gut microbiota has emerged as a critical factor in HCC development and *** normal conditions,BA metabolism is tightly regulated through a bidirectional interplay between gut microorganisms and *** gut microbiota plays a critical role in BA metabolism,and BAs are endogenous signaling molecules that help maintain liver and intestinal *** note,dysbiotic changes in the gut microbiota during pathogenesis and cancer development can disrupt BA homeostasis,thereby leading to liver inflammation and fibrosis,and ultimately contributing to HCC ***,understanding the intricate interplay between BAs and the gut microbiota is crucial for elucidating the mechanisms underlying *** this review,we comprehensively explore the roles and functions of BA metabolism,with a focus on the interactions between BAs and gut microorganisms in ***,therapeutic strategies targeting BA metabolism and the gut microbiota are discussed,including the use of BA agonists/antagonists,probiotic/prebiotic and dietary interventions,fecal microbiota transplantation,and engineered *** summary,understanding the complex BA-microbiota crosstalk can provide valuable insights into HCC development and facilitate the development of innovative therapeutic approaches for liver malignancy.

关键词： Bile acid gut microbiota hepatocellular carcinoma therapeutics microbiota modulation

Antibacterial Property of Cu Modified Stainless Steel by Plasma Surface Alloying

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Journal of Iron and Steel Research International 2012年第4期19卷 75-79页

作者： zhang xiang-yu HUANG Xiao-bo JIANG Li MA Yong FAN Ai-lan TANG Bin Research Institute of Surface Engineering Taiyuan University of Technology Taiyuan 030024 Shanxi China

Stainless steel（SS） is not recommended to be used in hospital environments for work surfaces and door furniture due to the lack of antibacterial *** this end,a novel SS surface modified layer with both a quick bacterial killing rate and relatively thick has been obtained by plasma surface alloying with *** microstructure,elements distribution and phase identification were analyzed by SEM,GDS,XRD and XPS.A spread plate method was adopted for evaluation of antibacterial property of specimens against Escherichia coli（***） and Staphylococcus aureus（***）.The experimental results demonstrate that the surface modified layer with the thickness of about 26 μm is uniform and *** layer is mainly composed of a mixture of pure Cu,expanded austenite phase and a few Fe3O4 *** Cu modified layer exhibits excellent antibacterial effects against *** and *** within 1 *** viable *** and *** was found after 3 h（100% killed）.The modified layer is relatively thick,hence it is expected that the Cu modified SS will have a durable antibacterial function

关键词： plasma alloying Cu antimicrobial AISI 304 stainless steel