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高速铁路动车运用所用地指标探讨

铁道标准设计 2024年第5期68卷 178-182页

作者：欧阳鹏张正舟李豫闻方宇中国国家铁路集团有限公司工程设计鉴定中心北京100844 中国铁路设计集团有限公司天津300308

动车运用所作为高速铁路的重要配套设施,是动车组整备、一二级检修、存放和临修等作业的重要场所。节约用地是工程设计的重要原则之一,在满足功能要求的同时,动车运用所总平面布置应力求用地紧凑、布局经济合理。按单股道及单车用地两... 详细信息

动车运用所作为高速铁路的重要配套设施,是动车组整备、一二级检修、存放和临修等作业的重要场所。节约用地是工程设计的重要原则之一,在满足功能要求的同时,动车运用所总平面布置应力求用地紧凑、布局经济合理。按单股道及单车用地两种方法探讨用地指标计算方法,结合既有动车运用所用地指标分析,在设施设置规模、设置方式等方面进行比较,综合确定动车运用所宜按单股道用地方法进行用地指标计算,同时提出用地指标标准建议。创新对动车运用所用地指标进行探讨,研究确定按单股道用地方法进行用地指标计算并提出标准建议,相关研究成果对动车运用所建设具有较强的参考借鉴意义。

关键词：高速铁路动车运用所用地指标总平面布置节约用地标准

土壤水分和种植密度对紫花苜蓿生物量分配的影响

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草业科学 2024年第9期41卷 2094-2103页

作者：蒋朝吴征江李春阳张振洲武文莉刘慧霞西北民族大学生命科学与工程学院甘肃兰州730000 甘南民族师范学院化学与生命科学系甘肃合作747000

为探寻生物量分配对不同土壤水分和种植密度互作的响应规律,为生产管理中通过种植密度和土壤含水量耦合管理来调控植物生物量分配,提高水分利用效率和植物生产力,完善植物适应环境因素的机制研究,本研究以紫花苜蓿(Medicago sativa)为材... 详细信息

为探寻生物量分配对不同土壤水分和种植密度互作的响应规律,为生产管理中通过种植密度和土壤含水量耦合管理来调控植物生物量分配,提高水分利用效率和植物生产力,完善植物适应环境因素的机制研究,本研究以紫花苜蓿(Medicago sativa)为材料,通过盆栽试验分析了不同土壤水分85%~90%(W_(1))、75%~80%(W_(2))、60%~65%(W_(3))、35%~40%(W_(4))的土壤饱和含水量和不同种植密度10(D_(1))、15(D_(2))、20(D_(3))株·盆^(−1)对紫花苜蓿生物量分配的影响。结果表明,土壤水分显著影响紫花苜蓿的叶生物量、茎生物量、单株地上生物量、地上生物量、地下生物量、根冠比(P<0.05),随土壤水分的减少,均呈先增加后降低趋势,峰值均出现在土壤水分含量为土壤饱和含水量的75%~80%时。种植密度显著影响紫花苜蓿单株地上生物量、地下生物量和根冠比(P<0.05),随种植密度增大,单株地上生物量呈先增高后降低趋势,种植密度为15株·盆^(−1)时,地下生物量和根冠比则呈增高趋势。土壤水分和种植密度互作只显著影响了紫花苜蓿的单株地上生物量(P<0.05),在土壤水分为土壤饱和含水量的75%~80%,种植密度为15株·盆^(−1)时,紫花苜蓿单株地上生物量有最大值,为5.00 g。这一结果说明紫花苜蓿可以通过调节地上、地下生物量的分配来适应土壤水分和种植密度条件,提高其水分利用效率和产量。

关键词：紫花苜蓿水分梯度密度梯度地上生物量地下生物量

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Ternary deep eutectic solvents catalyzed D-glucosamine self-condensation to deoxyfructosazine: NMR study

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Green Energy & Environment 2021年第2期6卷 261-270页

作者： Pengfei Liu Christian Marcus Pedersen Jiaojiao zhang Rui Liu zhenzhou zhang Xianglin Hou Yingxiong Wang Shanxi Engineering Research Center of Biorefinery Instiute of Coal ChemistryChinese Academy of Sciences27 South Taoyucn Road Taiyun030001China Center of Materials Science and Optoeletronics Engineering University of Chinese Academy of SciencesBejing100049China Department of Chemistny University of CopenhagenUniversitetsparken 5DK-2100 CopenhagenDenmark School of Chemical Engineering Zhengzhou University Zhengzhou450001China

Ternary deep eutectic solvents(TDESs) comprising choline chloride(Ch Cl), glycerol and L-arginine were synthesized as catalysts and solvents for the conversion of D-glucosamine(GlcNH_(2)) into deoxyfructosazine(DOF). The interactions between these three components in the prepared TDESs were studied by ^(1)H-,^(35)Cl-NMR spectra and ^(1)H diffusion-ordered spectroscopy(DOSY) measurements. The chemical shift changes of active hydrogen in the ^(1)H-NMR spectra of TDES system and widening of signals in the^(35)Cl-NMR spectra confirmed the hydrogen bonding interaction between the components, which was further supported by the decrease of diffusion coefficients(D) of the TDES components according to ^(1)H DOSY measurements. The influences of reaction temperature and L-arginine content in the TDESs on the yield of DOF were also studied. The experimental results have shown that when the molar ratio of Ch Cl, glycerol, and L-arginine was 1:2:0.1, DOF was the major product with a yield of 22.6% at 90℃ for 120 min. The chemical shift titration indicated that the carboxyl group of L-arginine in the TDES is the catalytical active site, so the mechanism of the catalytic reaction between Glc NH_(2) and the TDES was proposed. Moreover, a reaction intermediate, dihydrofructosazine, was identified in the self-condensation reaction of Glc NH_(2) by an in situ ^(1)H NMR technique.

关键词： Ternary deep eutectic solvents Hydrogen bonding NMR D-glucosamine Deoxyfructosazine

Ni/CeO_(2)催化剂上CO_(2)甲烷化反应本征动力学研究

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低碳化学与化工 2024年第8期49卷 123-130页

作者：范志辉岳燕燕张笑楠李新立张少康张振洲涂维峰韩一帆郑州大学化工学院河南郑州450001

CO_(2)加氢合成CH4(CO_(2)甲烷化)是CO_(2)高效、清洁转化的重要途径之一。尽管CO_(2)甲烷化的催化体系研究已较深入,但特定条件下CO_(2)甲烷化本征动力学的研究较少。采用燃烧法制备了Ni/CeO_(2)催化剂(Ni质量分数为10%),并通过加入内... 详细信息

CO_(2)加氢合成CH4(CO_(2)甲烷化)是CO_(2)高效、清洁转化的重要途径之一。尽管CO_(2)甲烷化的催化体系研究已较深入,但特定条件下CO_(2)甲烷化本征动力学的研究较少。采用燃烧法制备了Ni/CeO_(2)催化剂(Ni质量分数为10%),并通过加入内稀释剂(α-Al_(2)O_(3))制备了不同m(α-Al_(2)O_(3)):m(Ni/CeO_(2))的样品。考察了在温度为300℃、压力为1 MPa和空速为3×10^(6)mL/(g·h)的条件下,m(α-Al_(2)O_(3)):m(Ni/CeO_(2))=25:1样品(样品A)的CO_(2)甲烷化本征动力学。结合本征动力学测试、漫反射红外光谱、H_(2)-程序升温还原和H_(2)-程序升温脱附等对CO_(2)甲烷化本征反应动力学方程进行了深入分析。结果表明,样品A作用下的CH_(4)生成速率最高可达41.4mmol/(g·h)(H_(2)分压为400kPa,CO_(2)分压为120 kPa)。当CO_(2)分压为30~120 kPa时,CH_(4)生成速率随H_(2)分压的增大线性增长,并且不受CO_(2)分压或CO分压变化的影响。在该CO_(2)分压范围内,富氢环境可以显著提高催化剂的CO_(2)甲烷化催化活性。

关键词： CO_(2)甲烷化 Ni/CeO_(2)催化剂本征动力学

High Utility Periodic Frequent Pattern Mining in Multiple Sequences

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Computer Modeling in Engineering & Sciences 2023年第10期137卷 733-759页

作者： Chien-Ming Chen zhenzhou zhang Jimmy Ming-Tai Wu Kuruva Lakshmanna College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao266590China Department of Information Technology Vellore Institute of TechnologyVellore632014India

Periodic patternmining has become a popular research subject in recent years;this approach involves the discoveryof frequently recurring patterns in a transaction sequence. However, previous algorithms for periodic patternmining have ignored the utility (profit, value) of patterns. Additionally, these algorithms only identify periodicpatterns in a single sequence. However, identifying patterns of high utility that are common to a set of sequencesis more valuable. In several fields, identifying high-utility periodic frequent patterns in multiple sequences isimportant. In this study, an efficient algorithm called MHUPFPS was proposed to identify such patterns. To addressexisting problems, three new measures are defined: the utility, high support, and high-utility period sequenceratios. Further, a new upper bound, upSeqRa, and two new pruning properties were proposed. MHUPFPS usesa newly defined HUPFPS-list structure to significantly accelerate the reduction of the search space and improvethe overall performance of the algorithm. Furthermore, the proposed algorithmis evaluated using several *** experimental results indicate that the algorithm is accurate and effective in filtering several non-high-utilityperiodic frequent patterns.

关键词： Decision making frequent periodic pattern multi-sequence database sequential rules utility mining

NMR diffusion analysis of catalytic conversion mixtures from lignocellulose biomass using PSYCHE-iDOSY

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Green Energy & Environment 2023年第5期8卷 1409-1416页

作者： Qi Zhao Christian Marcus Pedersen Jiamin Wang Rui Liu Yuanli zhang Xiuyin Yan zhenzhou zhang Xianglin Hou Yingxiong Wang Shanxi Engineering Research Center of Biorefinery Institute of Coal ChemistryChinese Academy of Sciences27 South Taoyuan RoadTaiyuan030001China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China Department of Chemistry University of CopenhagenUniversitetsparken 5DK-2100CopenhagenDenmark School of Chemical Engineering Zhengzhou University Zhengzhou450001China Shanxi Inspection and Testing Center 106 Changzhi RoadTaiyuan030012China

The component analysis and structure characterization of complex mixtures of biomass conversion remain a challenging ***,developing effective and easy to use techniques is ***-ordered NMR spectroscopy(DOSY)is a non-selective and non-invasive method capable of achieving pseudo-separation and structure assignments of individual compounds from biomass mixtures by providing diffusion coefficients(D)of the ***,the conventional 1H DOSY NMR is limited by crowded resonances when analyzing complex mixtures containing similar chemical structure resulting in similar *** we describe the application of an advanced diffusion NMR method,Pure Shift Yielded by CHirp Excitation DOSY(PSYCHE-iDOSY),which can record high-resolution signal diffusion spectra efficiently separating compounds in model and genuine mixture samples from cellulose,hemicellulose and *** sets of isomers(D-glucose/D-fructose/D-mannose and 1,2-/1,5-pentadiol),homologous compounds(ethylene glycol and 1,2-propylene glycol),model compounds of lignin,and a genuine reaction system(furfuryl alcohol hydrogenolysis with ring opening)were successfully separated in the diffusion *** results show that the ultrahigh-resolution DOSY technique is capable of detecting and pseudo-separating the mixture components of C_(5)/C_(6) sugar conversion products and its derivative hydrogenation/hydrogenolysis from lignocellulose biomass.

关键词： Diffusion NMR Pure shift spectroscopy PSYCHE-iDOSY Mixture analysis Biomass

我国污泥处理处置行业政策及标准发展现状研究及建议

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环境与发展 2024年第3期36卷 1-6页

作者：韩景超张振洲李金波刘双龙张凯中电建生态环境集团有限公司广东深圳518102

本文主要梳理和研究我国污泥处理处置政策以及标准发展现状,分析存在的问题并提出相应的对策及建议,为构建和完善我国污泥处理处置政策体系、标准体系提供参考,进一步提高污泥处理处置技术水平,实现污泥绿色低碳处理处置,最大程度回收... 详细信息

本文主要梳理和研究我国污泥处理处置政策以及标准发展现状,分析存在的问题并提出相应的对策及建议,为构建和完善我国污泥处理处置政策体系、标准体系提供参考,进一步提高污泥处理处置技术水平,实现污泥绿色低碳处理处置,最大程度回收利用污泥能源和资源,支撑我国污泥处理处置行业高质量发展。

关键词：城镇污水厂污泥河湖污泥处理处置政策标准

ACE2/Ang-(1-7) signaling and vascular remodeling

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Science China(Life Sciences) 2014年第8期57卷 802-808页

作者： zhang zhenzhou CHEN LaiJiang ZHONG JiuChang GAO PingJin OUDIT Gavin Y. State Key Laboratory of Medical Genomics Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai Key Laboratory of Hypertension Shanghai Institute of Hypertension Department of Medicine University of Alberta Mazankowski Alberta Heart Institute

The renin-angiotensin system(RAS)regulates vascular tone and plays a critical role in vascular remodeling,which is the result of a complex interplay of alterations in vascular tone and *** of the RAS has led to important pharmacological tools to prevent and treat vascular diseases such as hypertension,diabetic vasculopathy and *** converting enzyme 2(ACE2)was recently identified as a multifunctional monocarboxypeptidase responsible for the conversion of angiotensin(Ang)II to Ang-(1-7).The ACE2/Ang-(1-7)signaling has been shown to prevent cellular proliferation,pathological hypertrophy,oxidative stress and vascular ***,the ACE2/Ang-(1-7)signaling is deemed to be beneficial to the cardiovascular system as a negative regulator of the *** addition of the ACE2/Ang-(1-7)signaling to the complexities of the RAS may lead to the development of novel therapeutics for the treatment of hypertension and other vascular *** present review considers recent findings regarding the ACE2/Ang-(1-7)signaling and focuses on its regulatory roles in processes related to proliferation,inflammation,vascular fibrosis and remodeling,providing proof of principle for the potential use of ACE2 as a novel therapy for vascular disorders related to vascular remodeling.

关键词： angiotensin converting enzyme 2 inflammation vascular remodeling angiotensin II oxidative stress

High efficient catalytic oxidation of 5-hydroxymethylfurfural into 2,5-furandicarboxylic acid under benign conditions with nitrogen-doped graphene encapsulated Cu nanoparticles

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Journal of Energy Chemistry 2020年第11期29卷 96-105页

作者： Chaoxin Yang Xiao Li zhenzhou zhang Bohan Lv Jiachun Li Zhenjian Liu Wanzhen Zhu Furong Tao Guangqiang Lv Yongxing Yang Shandong Provincial Key Laboratory of Molecular Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353ShandongChina Key Laboratory of Coal Processing and Efficient Utilization Ministry of EducationChina University of Mining and TechnologyXuzhou 221116JiangsuChina Engineering Research Center of Advanced Functional Material Manufacturing of Ministry of Education School of Chemical EngineeringZhengzhou University.Zhengzhou 450001HenanChina School of Chemistry and Chemical Engineering Shanxi UniversityTaiyuan 030006ShanxiChina

Selective oxidation of 5-hydroxymethylfurfual(HMF) to 2,5-furandicarboxylic acid(FDCA) as a bioplastics monomer is efficiently promoted by a simple system without noble-metal and base additives. In this work, graphene oxide(GO) was first synthesised by an electrochemical method with flexible graphite paper(FGP) as start carbon material, then, nitrogen-doped graphene(NG) layers encapsulated Cu nanoparticles(NPs) was prepared by one-step thermal treatment of GO supported Cu2+ in flowing NH3 atmosphere. Compared with NG supported Cu NPs prepared by the traditional impregnation method, enhanced catalytic activity was achieved over Cu/NG and an FDCA yield of 95.2% was achieved under mild reaction conditions with tert-butylhydroperoxide(t-BuOOH) as the oxidant. Control experiments with different catalysts and different addition procedure of t-BuOOH showed the yield of HMF and various intermediates during reaction. From the changing of intermediates concentrations and reaction rates, a reaction pathway through HMF-DFF-FFCA-FDCA was proposed. This work gives a more convenient, more green,more economical and effective method in encapsulated metal NPs preparation and high selectivity in HMF oxidation to FDCA under mild conditions.

关键词： Graphene oxide Encapsulated nanoparticles 5-hydroxymethylfurfual 2,5-furandicarboxylic acid Oxidation Noble-metal free