检索结果-南通市图书馆

Surface quality investigation in high-speed dry milling of Ti-6Al-4V by using 2D ultrasonic-vibration-assisted milling platform

引用

Advances in Manufacturing 2024年第2期12卷 349-364页

作者： jin Zhang Li Ling qian-Yue Wang Xue-feng Huang Xin-Zhen Kang Gui-Bao Tao Hua-Jun Cao College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing400044People’s Republic of China State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing400044People’s Republic of China Aerospace Research Institute of Materials and Processing Technology Beijing100076People’s Republic of China

Ultrasonic-vibration-assisted milling(UVAM)is an advanced method for the efficient and precise machining of difficult-to-machine materials in modern ***,the milling efficiency is limited because the ultrasonic vibration toolholder ER16 collet has a critical cutting ***,a 2D UVAM platform is built to ensure precision machining efficiency and improve the surface quality without changing the milling *** evaluate this 2D UVAM platform,ultrasonic-vibration-assisted high-speed dry milling(UVAHSDM)is performed to process a titanium alloy(Ti-6Al-4V)on the platform,and the milling temperature,surface roughness,and residual stresses are selected as the important indicators for performance *** results show that the intermittent cutting mechanism of UVAHSDM combined with the specific spindle speed,feed speed,and vibration amplitude can reduce the milling temperature and improve the texture of the machined *** with conventional milling,UVAHSDM reduces surface roughness and peak-groove surface profile values and extends the range of residual surface compressive stresses from−413.96 MPa to−600.18 *** excellent processing performance demonstrates the feasibility and validity of applying this 2D UVAM platform for investigating surface quality achieved under UVAHSDM.

关键词： 2D ultrasonic-vibration-assisted milling(UVAM)platform Ultrasonic-vibration-assisted high-speed dry milling(UVAHSDM) Milling temperature Surface roughness Residual stress

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Mechanistic insights into stepwise activation of malachite for enhancing surface reactivity and flotation performance

引用

International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2159-2172页

作者： Qicheng feng Wanming Lu Han Wang qian Zhang State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Mineral Resources Kunming University of Science and TechnologyKunming 650093China

Malachite is a common copper oxide mineral that is often enriched using the sulfidization-xanthate flotation ***,the direct sulfidization method cannot yield copper concentrate ***,a new sulfidization flotation process was developed to promote the efficient recovery of *** this study,Cu^(2+) was used as an activator to interact with the sample surface and increase its reaction sites,thereby strengthening the mineral sulfidization process and *** to single copper ion activation,the flota-tion effect of malachite significantly increased after stepwise Cu^(2+) *** potential,X-ray photoelectron spectroscopy(XPS),time-of-flight secondary ion mass spectroscopy(ToF-SIMS),scanning electron microscopy and energy dispersive spectrometry(SEM-EDS),and atomic force microscopy(AFM)analysis results indicated that the adsorption of S species was significantly enhanced on the mineral surface due to the increase in active Cu sites after Cu^(2+) stepwise ***,the proportion of active Cu-S spe-cies also increased,further improving the reaction between the sample surface and subsequent ***-transform infrared spec-troscopy(FT-IR)and contact angle tests implied that the xanthate species were easily and stably adsorbed onto the mineral surface after Cu^(2+) stepwise activation,thereby improving the hydrophobicity of the mineral ***,the copper sites on the malachite sur-face after Cu^(2+) stepwise activation promote the reactivity of the mineral surface and enhance sulfidization flotation of malachite.

关键词： malachite copper ions stepwise activation flotation mechanism enhanced sulfidization

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Quantum phase transition of the Jaynes-Cummings model

引用

Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 1-9页

作者： Cheng Liu jin-feng Huang Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Key Laboratory for Matter Microstructure and Function of Hunan ProvinceDepartment of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsInstitute of Interdisciplinary StudiesHunan Normal UniversityChangsha 410081China

Herein,we propose an experimentally feasible scheme to show the quantum phase transition of the Jaynes-Cummings(JC)model by modulating the transition frequency of a two-level system in a quantum Rabi model with strong *** tuning the modulation frequency and amplitude,the ratio of the effective coupling strength of the rotating terms to the effective cavity(atomic transition)frequency can enter the deep-strong coupling regime,while the counter-rotating terms can be ***,a deep-strong JC model is *** ratio of the coupling strength to resonance frequencies in the deep-strong JC model is two orders of magnitude larger than the corresponding ratio in the original quantum Rabi *** scheme can be employed in atom-cavity resonance and off-resonance cases,and it is valid over a broad *** nonzero average cavity photons of the ground state indicate the emergence of a quantum phase ***,we demonstrate the dependence of the phase diagram on the atom-cavity detuning and modulation *** the parameters used in our scheme are within the reach of current experimental *** scheme provides a new mechanism for investigating the critical phenomena of finite-sized systems without requiring classical field limits,thereby opening a door for studying fundamental quantum phenomena occurring in the ultrastrong and even deep-strong coupling regimes.

关键词： Jaynes-Cummings model quantum phase transition frequency modulation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Guaranteed Cost Attitude Tracking Control for Uncertain Quadrotor Unmanned Aerial Vehicle Under Safety Constraints

引用

IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1447-1457页

作者： qian Ma Peng jin Frank L.Lewis School of Automation Nanjing University of Science and TechnologyNanjing 210094China UTA Research Institute University of Texas at ArlingtonFort WorthTexas 76118 USA IEEE

In this paper,guaranteed cost attitude tracking con-trol for uncertain quadrotor unmanned aerial vehicle(QUAV)under safety constraints is ***,an augmented system is constructed by the tracking error system and reference *** transformation aims to convert the tracking control prob-lem into a stabilization control ***,control barrier function and disturbance attenuation function are designed to characterize the violations of safety constraints and tolerance of uncertain disturbances,and they are incorporated into the reward function as penalty *** on the modified reward function,the problem is simplified as the optimal regulation problem of the nominal augmented system,and a new Hamilton-Jacobi-Bellman equation is ***,critic-only rein-forcement learning algorithm with a concurrent learning tech-nique is employed to solve the Hamilton-Jacobi-Bellman equa-tion and obtain the optimal *** proposed algorithm can not only ensure the reward function within an upper bound in the presence of uncertain disturbances,but also enforce safety *** performance of the algorithm is evaluated by the numerical simulation.

关键词： Attitude tracking control quadrotor unmanned aerial vehicle(QUAV) reinforcement learning safety constraints uncertain disturbances.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Simultaneous purification of minor components in natural products using twin-column recycling chromatography with a step solvent gradient

引用

Chinese Journal of Chemical Engineering 2024年第5期69卷 212-219页

作者： Guangxia jin Yuxue Wu feng Wei School of Biological and Chemical Engineering NingboTech UniversityNingbo 315100China

The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar *** study introduces an optimized twin-column recycling chromatography method for the efficient and simultaneous purification of these elusive *** introducing water at a small flowing rate between the twin columns,a step solvent gradient is created,by which the leading edge of concentration band would migrate at a slower rate than the trailing edge as it flowing from the upstream to downstream ***,the band broadening is counterbalanced,resulting in an enrichment effect for those minor components in separation ***,two target substances,which showed similar peak position in high performance liquid chromatography(HPLC)and did not exceed 1.8%in crude paclitaxel were selected as target compounds for *** using the twin-column recycling chromatography with a step solvent gradient,a successful purification was achieved in getting the two with the purity almost 100%.We suggest this method is suitable for the separation of most components in natural produces,which shows higher precision and recovery rate compared with the common lab-operated separation ways for natural products(thin-layer chromatography and prep-HPLC).

关键词： Solvent gradient Twin-column recycling chromatography Purification Minor component Natural products

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Analysis of Phytochemical Constituents of Zuogui Wan in Rat Serum and its Effects on Early Embryonic Development of Mice

引用

World Journal of Traditional Chinese Medicine 2020年第3期6卷 324-330页

作者： Ya-Fei Guo Kai-Xia Xu Jie-Wei Hong Shuang Yin Xin Niu qian-jin feng Ying-Li Wang Institute of Chinese and Food Engineering Shanxi University of Chinese Medicine College of Basic Medical Sciences Shanxi University of Chinese MedicineJinzhong School of Basic Medical Sciences Beijing University of Chinese MedicineBeijingChina School of Chemical Engineering and Advanced Materials The University of AdelaideAdelaideAustralia

Objective:Zuogui Wan(ZGW)has been used as a typical prescription for tonifying kidney essence in traditional Chinese *** objective of this study is to elucidate the phytochemical constituents of ZGW-treated rat serum(ZGWRS)using ultra-performance liquid chromatography-electrospray ionization/quadrupole-time-of-flight high-definition mass spectrometry(UPLC-ESI-Q-TOF-MS).Methods:ZGW was administered to rats,and the phytochemical constituents in rat serum were determined using *** analysis in negative ion mode was adopted to characterize the chemical constituents of *** partial least squares discriminant analysis was applied for the discovery of constituents of ZGW that entered the serum of *** fertilized eggs collected from the same experiment were randomly divided into four groups,including the normal,40 mmol/L glucose,40 mmol/L glucose 5%control rat serum,and 40 mmol/L glucose 5%ZGWRS *** were cultivated at 37°C and 5%CO2 in a saturated humidity CO2 *** blastocyst rate and two-cell rate were used to evaluate the effects of ZGWRS on embryonic ***:Thirteen constituents were identified in the ZGWRS,among which sweroside,loganin,morroniside,loganic acid,and 8-epiloganic acid were from Fructus Corni(Shan Zhu Yu).5-Hydroxymethyl-2-furfural-glucuronide,2-H-5-hydroxymethyl-2-furfural-glucuronide,3-hydroxy-2,6,6-trimethyl-1-cyclohexene-1-carboxylic acid,andβ-D-ribofuranuronic acid methyl ester triacetate were from Radix Rehmanniae Preparata(Shu Di Huang).Coumaric acid was from Fructus Lycii(Gou Qi Zi).Kaempferol-3-beta-O-glucuronide and cuscutamine were from Semen Cuscutae(Tu Si Zi).The embryonic development was significantly inhibited using 40 mmol/L *** with the normal group,the blastocyst rate of the glucose group was *** blastocyst rate of the 40 mmol/L glucose 5%ZGWRS group was significantly higher than that of the glucose group,indicating that ZGWRS negates the

关键词： Orthogonal partial least squared discriminant analysis ultra-performance liquid chromatograph-electrospray ionization/quadrupole-time-of-flight high-definition mass spectrometry Zuogui Wan

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Causal temporal graph attention network for fault diagnosis of chemical processes

引用

Chinese Journal of Chemical Engineering 2024年第6期70卷 20-32页

作者： Jiaojiao Luo Zhehao jin Heping jin qian Li Xu Ji Yiyang Dai School of Chemical Engineering Sichuan UniversityChengdu 610065China China Three Gorges Corporation Beijing 100038China

Fault detection and diagnosis(FDD)plays a significant role in ensuring the safety and stability of chemical *** the development of artificial intelligence(AI)and big data technologies,data-driven approaches with excellent performance are widely used for FDD in chemical ***,improved predictive accuracy has often been achieved through increased model complexity,which turns models into black-box methods and causes uncertainty regarding their *** this study,a causal temporal graph attention network(CTGAN)is proposed for fault diagnosis of chemical processes.A chemical causal graph is built by causal inference to represent the propagation path of *** attention mechanism and chemical causal graph were combined to help us notice the key variables relating to fault *** in the Tennessee Eastman(TE)process and the green ammonia(GA)process showed that CTGAN achieved high performance and good explainability.

关键词： Chemical processes Safety Fault diagnosis Causal discovery Attention mechanism Explainability

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Exploring the role of interleukin-6 receptor blockade in epilepsy and associated neuropsychiatric conditions through a mendelian randomization study

引用

World Journal of Psychiatry 2024年第8期14卷 1244-1253页

作者： Yan-Mei Yu Gui-Hong jin Chong Zhong Hao qian Lei Wang feng Zhan Department of Pediatrics The First People's Hospital of ChuzhouChuzhou 239001Anhui ProvinceChina Department of Wenzhou Institute University of Chinese Academy of SciencesWenzhou 325000Zhejiang ProvinceChina

BACKGROUND The interplay between inflammation,immune dysregulation,and the onset of neurological disorders,including epilepsy,has become increasingly ***(IL)-6,a pro-inflammatory cytokine,is suspected to not only mediate traditional inflammatory pathways but also contribute to neuroinflammatory responses that could underpin neuropsychiatric symptoms and broader psychiatric disorders in epilepsy *** role of IL-6 receptor(IL6R)blockade presents an intriguing target for therapeutic intervention due to its potential to attenuate these *** conditions due to *** Mendelian randomization(MR)analysis employing single nucleotide poly-morphisms(SNPs)in the vicinity of the IL6R gene(total individuals=408225)was used to evaluate the putative causal relationship between IL6R blockade and epilepsy(total cases/controls=12891/312803),focal epilepsy(cases/controls=7526/399290),and generalized epilepsy(cases/controls=1413/399287).SNP weights were determined by their effect on C-reactive protein(CRP)levels and integrated using inverse variance-weighted meta-analysis as surrogates for IL6R *** address potential outlier and pleiotropic influences,sensitivity analyses were conducted employing a variety of MR methods under different modeling *** The genetic simulation targeting IL6R blockade revealed a modest but significant reduction in overall epilepsy risk[inverse variance weighting:Odds ratio(OR):0.827;95%confidence interval(CI):0.685-1.000;P=0.05].Subtype analysis showed variability,with no significant effect observed in generalized,focal,or specific childhood and juvenile epilepsy *** the primary inflammatory marker CRP,the findings also suggested potential non-inflammatory pathways mediated by IL-6 signaling contributing to the neurobiological landscape of epilepsy,hinting at possible links to neuroinflammation,psychiatric symptoms,and associated mental *** The i

关键词： Epilepsy Interleukin-6 receptor blockade Mendelian randomization Neuroinflammation Psychiatric disorders

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Remote copper-catalyzed enantioselective substitution of yne-thiophene carbonates

引用

Science China Chemistry 2024年第4期67卷 1175-1180页

作者： Hao-Dong qian Xiang Li Tingrui Yin Wei-feng qian Chunhui Zhao Cuiju Zhu Hao Xu CCNU-uOttawa Joint Research Centre Key Laboratory of Pesticides&Chemical Biology of Ministry of EducationInternational Joint Research Center for Intelligent Biosensing Technology and HealthCollege of ChemistryCentral China Normal UniversityWuhan 430079China

Here,we describe a strategy for the copper-catalyzed asymmetric heteroarylation of yne-thiophene carbonates with indoles via remote *** key to the success of this strategy lies in the design of the alkynyl group at the ortho-position of the heterocycle thiophene,enabling the formation of a triarylmethane moiety via very remote ***,the concept of remote copper-catalyzed asymmetric transformation extends not only to yne-allylic esters but also to yne-aryl *** reaction readily provides a diverse array of chiral triarylmethanes with high efficiency,enantioselectivity,and excellent functional group ***,facile follow-up transformations underscore their potential utility in the synthesis of various enantioenriched building *** mechanistic studies support the plausibility of the remote substitution pathway.

关键词： remote substitution copper catalyst asymmetric catalysis triaryl methanes

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Biomimetic chitin hydrogel via chemical transformation

引用

Nano Research 2024年第2期17卷 771-777页

作者： Rui-Rui Liu qian-qian Shi Yu-feng Meng Yong Zhou Li-Bo Mao Shu-Hong Yu Division of Nanomaterials&Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China College&Hospital of Stomatology Key Laboratory of Oral Diseases Research of Anhui ProvinceAnhui Medical UniversityHefei 230032China Department of Dental Implantology College&Hospital of StomatologyAnhui Medical UniversityHefei 230032China

Chitin hydrogel has been recognized as a promising material for various biomedical applications because of its biocompatibility and ***,the fabrication of strong chitin hydrogel remains a big challenge because of the insolubility of chitin in many solvents and the reduced chain length of chitin regenerated from *** herein introduce the fabrication of chitin hydrogel with biomimetic structure through the chemical transformation of chitosan,which is a water-soluble deacetylated derivative of *** reacetylation of the amino group in chitosan endows the obtained chitin hydrogel with outstanding resistance to swelling,degradation,extreme temperature and pH conditions,and organic *** chitin hydrogel has excellent mechanical properties while retaining a high water content(more than 95 wt.%).It also shows excellent antifouling performance that it resists the adhesion of proteins,bacteria,blood,and ***,as the initial chitosan solution can be feasibly frozen and templated by ice crystals,the chitin hydrogel structure can be either nacre-like or wood-like depending on the freezing method of the precursory chitosan *** to these anisotropic structures,such chitin hydrogel can exhibit anisotropic mechanics and mass transfer *** current work provides a rational strategy to fabricate chitin hydrogels and paves the way for its practical applications as a superior biomedical material.

关键词： chitin hydrogel biomimetic structure chemical stability mechanical strength antifouling

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：