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交通企业司库体系建设研究

内蒙古公路与运输 2024年第3期 54-58页

作者：李志清内蒙古交通集团有限公司内蒙古呼和浩特010010

司库作为一种先进的管理思想和管理模式,以提升资金运营效率、降低资金成本、防控资金风险为目标,是当前交通企业财务创新管理的重要工具。司库体系是以服务战略、支撑业务、创造价值为导向,对企业资金等金融资源进行实时监控和统筹调... 详细信息

司库作为一种先进的管理思想和管理模式,以提升资金运营效率、降低资金成本、防控资金风险为目标,是当前交通企业财务创新管理的重要工具。司库体系是以服务战略、支撑业务、创造价值为导向,对企业资金等金融资源进行实时监控和统筹调度的现代企业治理机制。文章以内蒙古交通集团有限公司为例,基于司库管理体系的发展趋势和建设要求,从集团基本情况、财务管理现状及司库主要内容和资源现状出发,理清司库体系建设的总体规划、目标、路径等思路,提出司库体系建设策略,为加快建立具有行业特色、适应内蒙古交通集团需要的司库体系提供一定参考。

关键词：交通企业司库体系财务管理资金管理

Classification of complete 3-dimensional self-shrinkers in the Euclidean space R^(4)

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Science China Mathematics 2024年第4期67卷 873-882页

作者： qing-Ming Cheng zhi li Guoxin Wei Department of Applied Mathematics Faculty of ScienceFukuoka UniversityFukuoka 814-0180Japan College of Mathematics and Information Science Henan Normal UniversityXinxiang 453007China School of Mathematical Sciences South China Normal UniversityGuangzhou 510631China

In this paper,we completely classify 3-dimensional complete self-shrinkers with the constant norm S of the second fundamental form and the constant f3in the Euclidean space R^(4),where hij’s are components of the sec... 详细信息

关键词： mean curvature ow self-shrinker the generalized maximum principle

Influence of friction-lubrication characteristics varying with rolling speed on instability of chatter and slip in cold tandem rolling process

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Journal of Iron and Steel Research International 2024年第4期31卷 894-908页

作者： Yan-li Xin zhi-ying Gao Bo Tian qing-dong Zhang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China

In the high-speed cold tandem rolling process of thin plate,chatter or slip instability gives rise to the deterioration of equipment and product *** instability behavior is closely related to interfacial friction-lubrication con-dition which is generally characterized by the friction ***,with higher and higher speed requirements,the commonly used model of friction coefficient is no longer applicable and accurate.A novel approach is suggested to calculate the speed-dependent friction coefficient,in which the viscosity-pressure-temperature effects of the lubricant,surface roughness states of work rolls and rolled piece are comprehensively involved and the mixed flm lubrication theory is ***,the influences of friction coefficient on the instability of slip and chatter are investigated for a five-stand cold tandem rolling *** one side,the critical friction coefficient for each stand is determined by calculating the corresponding slip factor;on the other hand,the friction coefficient varying with rolling speed is combined with the model of theoretical critical rolling speed presented under constant friction coefficient,so that the speed threshold is ***,the stable and unstable regions corresponding to the rear three stands are individually discussed,and the technical strategies are proposed to suppress both slip and chatter frequently occurring in the actual rolling process.

关键词： Cold tandem rolling:Oil film thickness Speed-dependent friction coefficient-Slip:Chatter

Development and validation of a prognostic immunoinflammatory index for patients with gastric cancer

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World Journal of Gastroenterology 2024年第24期30卷 3059-3075页

作者： zhi-Chang Ba Xi-qing Zhu zhi-Guo li Yuan-Zhou li Department of Radiology Harbin Medical University Cancer HospitalHarbin 150081Heilongjiang ProvinceChina Department of Gastrointestinal Surgery Harbin Medical University Cancer HospitalHarbin 150081Heilongjiang ProvinceChina

BACKGROUND Studies have demonstrated the influence of immunity and inflammation on the development of *** single biomarkers of immunity and inflam-mation have been shown to be clinically predictive,the use of biomarkers integrating both to predict prognosis in patients with gastric cancer remains to be *** To investigate the prognostic and clinical significance of inflammatory biomarkers and lymphocytes in patients undergoing surgical treatment for gastric *** Univariate COX regression analysis was performed to identify potential prognostic factors for patients with gastric cancer undergoing surgical *** absolute shrinkage and selection operator-COX(LASSO-COX)regression analysis was performed to integrate these factors and formulate a new prognostic immunoinflammatory index(PII).The correlation between PII and clinical charac-teristics was statistically *** incorporating the PII score were devised and validated based on the time-dependent area under the curve and decision curve *** Patients exhibiting elevated neutrophil-to-lymphocyte ratio,platelet-to-lymphocyte ratio,and systemic immune inflammatory index displayed inferior progression-free survival(PFS)and overall survival(OS).Conversely,low levels of CD3(+),CD3(+)CD8(+),CD4(+)CD8(+),and CD3(+)CD16(+)CD56(+)T lymphocytes were associated with improved PFS and OS,while high CD19(+)T lymphocyte levels were linked to worse PFS and *** PII score demonstrated associations with tumor characteristics(primary tumor site and tumor size),establishing itself as an independent prognostic factor for both PFS and ***-dependent area under the curve and decision curve analysis affirmed the effectiveness of the PII-based nomogram as a robust prognostic predictive *** PII may be a reliable predictor of prognosis in patients with gastric cancer undergoing surgical treatment,and it offers insights into cancer-related immune-inflammatory re

关键词： Gastric cancer Immunity Inflammation Prognosis Nomogram

Metal/covalent organic frameworks for aqueous rechargeable zinc-ion batteries

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Science China Chemistry 2024年第1期67卷 247-259页

作者： Hu Hong Xun Guo Jiaxiong Zhu Zhuoxi Wu qing li Chunyi zhi Department of Materials Science and Engineering City University of Hong KongHong Kong 999077China

lithium-ion batteries(liBs)have become one of the most successful energy storage systems due to their high operating voltage,high energy density,and long cycle ***,with the widespread use of liBs in recent decades,lithium resources are at risk of being ***,it is necessary to find a substitute for liBs to meet the needs of future large-scale energy storage *** of their competitiveness,low cost,and high safety,aqueous rechargeable zinc-ion batteries(ARZIBs)are regarded as promising components in the post-lithium-ion-battery *** the tunable composition,ordered porous channels,and controllable structure of metal-organic frameworks(MOFs)and covalent organic frameworks(COFs),these frameworks are viewed as potential materials for developing high-performance *** this review,we focus on the recent developments in the applications of MOF-/COF-based materials in ARZIBs,including in electrode materials,anode modifications,separators,and solid *** then focus on the critical factors and optimization techniques of MOF-/COF-based materials that affect the performance of ***,we conclude with some projections for the expansion of ARZIBs containing MOF-/COF-based materials.

关键词： metal/covalent organic frameworks aqueous zinc-ion batteries electrode materials anode modifications separators electrolytes

Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network

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Petroleum Science 2024年第1期21卷 621-640页

作者： Xue-Qiang Zhang qing-lin Cheng Wei Sun Yi Zhao zhi-Min li Key Lab of Ministry of Education for Enhancing the Oil and Gas Recovery Ratio Northeast Petroleum UniversityDaqing163318HeilongjiangChina China Petroleum Pipeline Material and Equipment Co. LtdLangfang065000HebeiChina Research Institute of Petroleum Engineering and Technology Sinopec Northwest Oilfield CompanyUrumqi830011XinjiangChina

As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex *** is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency *** this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is *** with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation *** comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are *** the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy *** entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their ***,the weak links in energy utilization are identified,and energy conservation and consumption reduction are *** above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems.

关键词： Crude oil gathering and transportation system GA-BP neural network Energy efficiency evaluation TOPSIS evaluation method Energy saving and consumption reduction

Dynamic Sulfur-Rich Polymers from Elemental Sulfur and Epoxides

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Chinese Journal of Polymer Science 2024年第10期42卷 1479-1487,I0010页

作者： Ke-Xiang Chen Chen-Hui Cui Zhen li Ting Xu Hao-qing Teng zhi-Yuan He Yin-Zhou Guo Xiao-qing Ming zhi-Shen Ge Yan-Feng Zhang Tie-Jun Wang School of Chemistry Engineering Research Center of Energy Storage Materials and DevicesMinistry of EducationXi’an Jiaotong UniversityXi’an710049China State Key Lab for Strength and Vibration of Mechanical Structures Department of Engineering MechanicsXi’an Jiaotong UniversityXi’an710049China

Sulfur-containing dynamic polymers had attracted significant attention due to their unique chemical structures with high *** sulfur, an inexpensive industrial waste product, to synthesize dynamic polysulfide polymers through reverse vulcanization has been a notable approach. However, this method required high temperatures and resulted in the release of unpleasant oders. In this study, we presented a robust method for the preparation of sulfur-rich polymers with dynamic polysulfide bonds from elemental sulfur and inexpensive epoxide monomers via a one-pot strategy at the mild room temperature. Different types of polysulfide molecules and polymers were synthesized by reacting various epoxide compounds with sulfur, along with the investigation of their structures and dynamic behaviors. It was noteworthy that the obatined polymers prepared from m-(2,3-epoxypropoxy)-N,N-bis(2,3-epoxypropyl)aniline and elemental sulfur exhibit multiple dynamic behaviors, including polysulfide metathesis and polysulfide-thiol exchange, enabling their rapid stress relaxation, self-healing, reprocessing and degradable properties of the cross-linked polymer. More importantly, the hydroxyl groups at the side chains from epoxide ring opening exhibited potential transesterification. This work provided a facile strategy for designing dynamic sulfur-rich polymers via a mild synthesis route.

关键词： Elemental sulfur Sulfur-containing polymer Dynamic covalent bond Dynamic polymer

Prediction of contact resistance of electrical contact wear using different machine learning algorithms

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Friction 2024年第6期12卷 1250-1271页

作者： Zhen-bing CAI Chun-lin li Lei YOU Xu-dong CHEN li-ping HE Zhong-qing CAO zhi-nan ZHANG Tribology Research Institute Southwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

H62 brass material is one of the important materials in the process of electrical energy transmission and signal transmission,and has excellent performance in all *** the wear behavior of electrical contact pairs is particularly complex when they are in service,we evaluated the effects of load,sliding velocity,displacement amplitude,current intensity,and surface roughness on the changes in contact *** learning(ML)algorithms were used to predict the electrical contact performance of different factors after wear to determine the correlation between different factors and contact *** forest(RF),support vector regression(SVR)and BP neural network(BPNN)algorithms were used to establish RF,SVR and BPNN models,respectively,and the experimental data were trained and *** was proved that BP neural network model could better predict the stable mean resistance of H62 brass alloy after *** analysis shows that the load and current have great influence on the predicted electrical contact *** wear behavior of electrical contacts is influenced by factors such as load,sliding speed,displacement amplitude,current intensity,and surface roughness during *** learning algorithms can predict the electrical contact performance after wear caused by these *** results indicate that an increase in load,current,and surface roughness leads to a decrease in stable mean resistance,while an increase in displacement amplitude and frequency results in an increase in stable mean resistance,leading to a decline in electrical contact *** reduce testing time and costs and quickly obtain the electrical contact performance of H62 brass alloy after wear caused by different factors,three algorithms(random forest(RF),support vector regression(SVR),and BP neural network(BPNN))were used to train and test experimental results,resulting in a machine learning model suitable for predicting the stable mean

关键词： electrical contact wear contact resistance machine learning(ML) neural network

Multi-physical fields distribution in billet during helical electromagnetic stirring:A numerical simulation research

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China Foundry 2024年第1期21卷 51-59页

作者： Dong Pan qing-tao Guo Kai-lun Zhang Fu-zhi Yu Yu-ying li Yu-bao Xiao State Key Laboratory of Metal Materials for Marine Equipment and Application Anshan 114009LiaoningChina Ansteel Beijing Research Institute Co. Ltd.Beijing 102200China

Electromagnetic stirring is one of the widely applied techniques to modify the quality of casting *** from conventional rotate stirring,the helical stirring is more professional in assisting multi-dimensional flow of molten metal and eliminating solidification *** this study,the single-winding helical stirring(SWHS)was introduced,offering advantages such as smaller volume and lower electromagnetic shielding compared to traditional helical stirring *** a comprehensive numerical simulation,the stirring parameters of SWHS were adjusted to yoke inclination angle of 43°and frequency of 12 *** higher electromagnetic force and flow velocity in drawing direction,as well as the lower temperature gradient induced by the SWHS,are positive factors for homogeneous solidification of *** experimental results on Al-8%Si alloy and 0.4%C-1.1%Mn steel demonstrate that compared to rotate stirring,the SWHS process can induce better billet quality and is more effective in accelerating the equiaxed expansion and reducing element *** SWHS process can enhance the equiaxed ratio of the billet by 58.3%and reduce segregation degree of carbon element by 10.97%.Consequently,SWHS holds great promise as a potential approach for improving the quality of continuous casting billets.

关键词： billet electromagnetic stirring helical solidification element segregation numerical simulation