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Analysis on composition and inclusions of ballpoint pen tip steel

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International Journal of Minerals,Metallurgy and Materials 2018年第4期25卷 420-428页

作者： qian-kun yang Ping Shen Dong Zhang Yan-xin Wu Jian-xun Fu State Key Laboratory of Advanced Special Steel Shanghai Key Laboratory of Advanced Ferrometallurgy School of Materials Science and Engineering Shanghai University

Ballpoint pen tip steel, a super free-cutting stainless steel, exhibits excellent corrosion resistance and good machining properties. In this study, inductively coupled plasma spectroscopy, metallographic microscopy, and scanning electron microscopy were used to determine the elemental contents in five ballpoint pen tips and their components, morphologies, and inclusion distributions. The results showed that the steels were all S–Pb–Te super free-cutting ferritic stainless steel. The free-cutting phases in the steels were mainly Mn S, Pb, and small amounts of Pb Te. Mn S inclusions were in the form of chain distributions, and the aspect ratio of each size inclusion in the chain was small. The stress concentration effect could substantially reduce the cutting force when the material was machined. Some of the Pb was distributed evenly in the steel matrix as fine particles（1–2 μm）, and the rest of the Pb was distributed at the middle or at both ends of the Mn S inclusions. The Pb plays a role in lubrication and melting embrittlement, which substantially increases the cutting performance. Pb Te was also usually distributed in the middle and at both ends of the Mn S inclusions, and Te could convert the sulfides into spindles, thereby improving the cutting performance of the steel.

关键词： ballpoint pen tip free-cutting stainless steel inclusions lead tellurium

A new era of mutation rate analyses: Concepts and methods

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Zoological Research 2024年第4期45卷 767-780页

作者： kun Wu Danqi Qin yang qian Haoxuan Liu Center for Evolutionary&Organismal Biology and the Fourth Affiliated Hospital of Zhejiang University Zhejiang University School of MedicineHangzhouZhejiang 310058China

The mutation rate is a pivotal biological characteristic,intricately governed by natural selection and historically garnering considerable *** advances in high-throughput sequencing and analytical methodologies have profoundly transformed our understanding in this domain,ushering in an unprecedented era of mutation rate *** paper aims to provide a comprehensive overview of the key concepts and methodologies frequently employed in the study of mutation *** examines various types of mutations,explores the evolutionary dynamics and associated theories,and synthesizes both classical and contemporary ***,this review comprehensively explores recent advances in understanding germline and somatic mutations in animals and offers an overview of experimental methodologies,mutational patterns,molecular mechanisms,and driving forces influencing variations in mutation rates across species and ***,it proposes several potential research directions and pressing questions for future investigations.

关键词： Mutation rate Somatic mutations Germline mutations Animal

Micro-sized nanoaggregates:Spray-drying-assisted fabrication and applications

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Particuology 2024年第2期85卷 22-48页

作者： Dan-Lei yang Rong-kun Liu Yan Wei qian Sun Jie-Xin Wang School of Life Sciences and Chemical Engineering Jiangsu Second Normal UniversityNanjing210013China State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing100029China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology School of Chemistry and Chemical EngineeringGuangxi UniversityNanning530004China

The applications of nanoparticles suffer from their extremely small size and intrinsic trend of *** nanoparticles to form micro-sized nanoaggregates(MNAs)with increased size,ordered structure,as well as controllable size,shape,and morphology is a crucial step in various fields of science and technology to maintain the unique characteristics of nanoparticles while obtaining greatly enhanced or new performance at the *** structure of MNAs prominently affects their functionality,which is determined by the arrangement of nanoparticles and the interaction between primary *** methods have been proposed to prepare the MNAs,in which spray-drying technology stands out considering the feasibility,scalability for industry,cost,and *** assembly of nanoparticles through spray-drying under tunable process parameters yields diverse physical properties and structural arrangements of nanoparticles of the MNAs,they therefore exhibit enormous potential in a wide range of application *** review presents the construction and applications of spray-dried *** factors that influence the size,morphology,and structure of the MNAs are discussed in *** addition,the outstanding application performance resulting from the tightly packed nanoparticles in regular-shaped MNAs obtained by the spray-drying process is illustrated.

关键词： Spray-drying Micro-sized nanoaggregates Applications

Advancements in synthetic and electrocatalytic exploitation of guest-host intercalated 2D materials

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Progress in Natural Science:Materials International 2024年第3期34卷 454-469页

作者： qian yang kun Wang Meiling Zhang Feihong Du Jiayang Li Chen Zheng Jinyang Li School of Chemistry Southwest Jiaotong University Yibin Institute of Southwest Jiaotong University

The emergence and development of layered materials have shown great promise for many applications, especially in recent years, the effective modulation of the physicochemical properties of layered materials by intercalation chemistry has led to great potential in material design. In this paper, we review the reaction mechanisms of different guest species(metal atoms/ions, organic molecules/ions, inorganic molecules and inorganic ions)intercalated into the host layered materials as well as the recent progress. It is also reviewed that layered intercalated materials with controllable structure and tunable physicochemical properties can be prepared through the occurrence of interactions between different subjects and guests. The specific applications of intercalation chemistry in the field of electrocatalysis, such as the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction and other electrocatalytic reactions, are then discussed, with emphasis on the mechanism of the improved catalytic activity and stability of the layered materials after guest intercalation.

关键词： Electrocatalysis Guest species Intercalation chemistry Layered materials

The Research to Quality Supervision and Management of Power Enterprises

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International Journal of Technology Management 2014年第3期 61-62页

作者： qian kun Zhang Shiwei yang Qingshan State Grid of Electric Power Company Supplies company in Shandong Province Jinan 250001

Intensive in-depth development of resources, centralized purchasing and gradually expand under the category of environment, this paper studies how to use information technology tools to construction quality supervision and management system that focuses on the quality of supervision and project management, quality control process management, quality monitoring statistics report management, platform management-related content in four areas. Through the construction quality supervision and management system, to better enhance the quality of electric power enterprise management level, to ensure that the material quality, quantity of time and supplies. strengthening quality supervision and management can not only effectively reduce material procurement costs, but also enhance the competitiveness of enterprises.

关键词： power companies quality monitoring prograna Quality Supervision Process Management

Realizing methanol synthesis from CO and water via the synergistic effect of Cu^(0)/Cu^(+)over Cu/ZrO_(2) catalyst

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Journal of Energy Chemistry 2024年第6期93卷 126-134,I0004页

作者： Yuan Fang Fan Wang yang Chen qian Lv kun Jiang Hua yang Huibo Zhao Peng Wang Yuyan Gan Lizhi Wu Yu Tang Xinhua Gao Li Tan Institute of Molecular Catalysis and In Situ/Operando Studies Fujian Key Laboratory of Electrochemical Energy Storage MaterialsState Key Laboratory of Photocatalysis on Energy and EnvironmentCollege of ChemistryFuzhou UniversityFuzhou 350108FujianChina Leibniz-Institut für Katalyse e.V.an der Universität Rostock Albert-Einstein Strasse 9118059 RostockGermany Department of Chemistry Tsinghua UniversityBeijing 100084China State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021Ningxi1China

The optimizing utilization of ca rbon resources has drawn wide attention all over the world,while exploiting the high-efficiency catalytic routes remains a ***,a direct methanol synthesis route is realized from pure CO and H_(2)O over 10%Cu/t-ZrO_(2) catalyst,where the time yield of methanol is144.43 mmol mol_(Cu)^(-1)h^(-1)and the methanol selectivity in hydrocarbons is 100%,The Cu species highly dispersed in the t-ZrO_(2) support lead parts of them in the cationic *** Cu^(+)sites contribute to the dissociation of H_(2)O,providing the H*source for methanol synthesis,while the formed Cu^(0) sites promote the absorption and transfer of H*during the ***,the H_(2)O is even a better H resource than H_(2) due to its better dissociation effectivity in this catalytic *** present work offers a new approach for methanol synthesis from CO and new insight into the process of supplying H donor.

关键词： H_(2)O CO Methanol Cu-based catalysts t-ZrO_(2)

Detecting somatisation disorder via speech:introducing the Shenzhen Somatisation Speech Corpus

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Intelligent Medicine 2024年第2期4卷 96-103页

作者： kun qian Ruolan Huang Zhihao Bao yang Tan Zhonghao Zhao Mengkai Sun Bin Hu Björn W.Schuller Yoshiharu Yamamoto Key Laboratory of Brain Health Intelligent Evaluation and Intervention Ministry of EducationBeijing Institute of TechnologyBeijing 100081China School of Medical Technology Beijing Institute of TechnologyBeijing 100081China The First School of Clinical Medicine Southern Medical UniversityGuangzhouGuangdong 510515China Department of Neurology Shenzhen University General HospitalShenzhenGuangdong 518055China Group on Language Audio&MusicImperial College LondonLondon SW72AZUK Embedded Intelligence for Health Care and Wellbeing University of AugsburgAugsburg 86159Germany Educational Physiology Laboratory Graduate School of EducationThe University of TokyoTokyo 113-0033Japan

Objective Speech recognition technology is widely used as a mature technical approach in many *** the study of depression recognition,speech signals are commonly used due to their convenience and ease of *** speech recognition is popular in the research field of depression recognition,it has been little studied in somatisation disorder *** reason for this is the lack of a publicly accessible database of relevant speech and benchmark *** this end,we introduced our somatisation disorder speech database and gave benchmark *** By collecting speech samples of somatisation disorder patients,in cooperation with the Shenzhen University General Hospital,we introduced our somatisation disorder speech database,the Shenzhen Somatisation Speech Corpus(SSSC).Moreover,a benchmark for SSSC using classic acoustic features and a machine learning model was proposed in our *** To obtain a more scientific benchmark,we compared and analysed the performance of different acoustic features,i.e.,the full ComPare feature set,or only Mel frequency cepstral coefficients(MFCCs),fundamental frequency(F0),and frequency and bandwidth of the formants(F1-F3).By comparison,the best result of our benchmark was the 76.0%unweighted average recall achieved by a support vector machine with formants F1–*** The proposal of SSSC may bridge a research gap in somatisation disorder,providing researchers with a publicly accessible speech *** addition,the results of the benchmark could show the scientific validity and feasibility of computer audition for speech recognition in somatization disorders.

关键词： Somatisation disorder Machine learning Healthcare Computer audition

Drug delivery systems for colorectal cancer chemotherapy

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Chinese Chemical Letters 2024年第2期35卷 163-175页

作者： Wen Chen kun Shi Yan Yu Peipei yang Zhongwu Bei Dong Mo Liping Yuan Meng Pan Yu Chen Zhiyong qian Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu 610041China

Colorectal cancer causes the third most common type of malignant tumors with high morbidity and *** is currently one of the most effective and common treatments for colorectal ***,the poor water solubility of some chemotherapeutics,untargeted drug delivery,and the undesirable systemic side effects of conventional treatment remain the major issues for colorectal cancer ***,drug delivery systems(DDS)based on biomaterials have been widely investigated and found to be capable of resolving those issues with good ***,the main goal of this review is to summarize and discuss the progress and potential advantages of different DDS for colorectal cancer *** not only reviewed the nanocarriers used to improve the solubility of chemotherapeutics,including liposomes,micelles,and nanoparticles,but also discussed targeted DDS based on specific ligand-receptor recognition and tumor microenvironmental stimulus ***,locally administered systems based on hydrogels and microspheres,which have been shown to increase drug accumulation at the tumor site while decreasing systemic toxicity,were also *** provides a good option for improving the efficacy of chemotherapy in the treatment of colorectal cancer.

关键词： Colorectal cancer Chemotherapy Drug delivery systems Solubility Targeted Local administration

Oncological features and prognosis of colorectal cancer in human immunodeficiency virus-positive patients: A retrospective study

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 29-39页

作者： Fu-Yu yang Fan He De-Fei Chen Cheng-Lin Tang Saed Woraikat Yao Li kun qian Department of Gastrointestinal Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of General Surgery Chongqing Public Health Medical CenterChongqing 400036China

BACKGROUND Due to the prolonged life expectancy and increased risk of colorectal cancer(CRC)among patients with human immunodeficiency virus(HIV)infection,the prognosis and pathological features of CRC in HIV-positive patients require *** To compare the differences in oncological features,surgical safety,and prognosis between patients with and without HIV infection who have CRC at the same tumor stage and *** In this retrospective study,we collected data from HIV-positive and-negative patients who underwent radical resection for *** random stratified sampling,24 HIV-positive and 363 HIV-negative patients with colorectal adenocarcinoma after radical resection were *** propensity score matching,we selected 72 patients,matched 1:2(HIV-positive:negative=24:48).Differences in basic characteristics,HIV acquisition,perioperative serological indicators,surgical safety,oncological features,and long-term prognosis were compared between the two *** Fewer patients with HIV infection underwent chemotherapy compared to patients ***-positive patients had fewer preoperative and postoperative leukocytes,fewer preoperative lymphocytes,lower carcinoembryonic antigen levels,more intraoperative blood loss,more metastatic lymph nodes,higher node stage,higher tumor node metastasis stage,shorter overall survival,and shorter progression-free survival compared to patients who were *** Compared with CRC patients who are HIV-negative,patients with HIV infection have more metastatic lymph nodes and worse long-term survival after *** treatment options for HIV-positive patients with CRC should be explored.

关键词： Colorectal cancer Human immunodeficiency virus Propensity score matching Oncological features Surgical safety Prognosis