检索结果-南通市图书馆

Chinese Chemical Letters 2024年第2期35卷 527-533页

作者： Yan-Hu Wang Ke-wei Tong Chao-qin Chen jing Du Peng Yang College of Chemistry and Chemical Engineering Advanced Catalytic Engineering Research Center of the Ministry of EducationHunan UniversityChangsha 410082China College of Chemistry and Materials Science Testing and Analysis CenterHebei Normal UniversityShijiazhuang 050024China

A bottleneck in biomimetic synthesis consists in the full copy of,for example,the hierarchical structure of proteins directed by weak *** contrast with covalent bonds bearing definite orientation and high stability,weak intermolecular forces within a continuous dynamic equilibrium can be hardly tamed for molecular *** this endeavor,a ligand-dominated strategy that embodies tunable electrostatic repulsion andπ···πstacking was first employed to shape polyoxovanadate-based metal-organic polyhedra(VMOPs).Structural evolution involving transformation,interlock,and discovery of an unprecedented prototype of the Star of David was hence *** only as a handy tool for the primary structural control over VMOPs,these weak forces allow for an advanced management on the spatial distribution of such manmade macromolecules as well as the associated physicochemical behaviors,representing an ideal model for simulating and interpreting the conformation-function relationship of proteins.

关键词： Polyoxometalates Polyoxovanadates Metal-organic polyhedron Interlock Weak intermolecular forces

高压氧或高浓度氧在预防和治疗噪声性听觉损伤中的作用

在线全文

学校读者我要写书评

暂无评论

声学学报 1986年第3期 129-135页

作者：史秀凤胡正元曹慧琴魏晶王曦海军医学研究所

本文报道豚鼠在噪声暴露前后吸2atm或latm纯氧对噪声性听觉损伤的影响。暴露噪声是1/3oct窄带噪声,中心频率1000Hz,强度136dB作用1h。在噪声暴露前或暴露后吸2atm纯氧可以减小噪声引起的永久性听阈偏移(对短声)。吸2atm纯氧所起的作用(... 详细信息

本文报道豚鼠在噪声暴露前后吸2atm或latm纯氧对噪声性听觉损伤的影响。暴露噪声是1/3oct窄带噪声,中心频率1000Hz,强度136dB作用1h。在噪声暴露前或暴露后吸2atm纯氧可以减小噪声引起的永久性听阈偏移(对短声)。吸2atm纯氧所起的作用(预防吸氧一次或治疗吸氧六次,每次1h),相当于把噪声强度降低1OdB(从136dB降至126dB。预防吸氧(暴露前吸氧)比治疗吸氧(暴露后吸氧)效果好。吸2atm纯氧比latm有效。文中讨论了吸高压氧或高浓度氧在预防和治疗噪声性听觉损伤中的某些机理。

关键词：噪声暴露豚鼠纯氧高浓度氧荷兰猪听阈偏移噪声性听觉损伤高压氧

Progress of organic magnetic materials

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2019年第7期62卷 22-33页

作者： Mengmeng wei Yingcai Fan wei qin State Key Laboratory of Crystal Materials School of Physics Shandong University School of Information and Electronic Engineering Shandong Technology and Business University

Over the past years, the development of magnetic materials has been intensively explored, both for fundamental research and technological applications. Particularly, several materials with large magnetoresistance effect have received significant *** this study, we provide an analysis of the progress of organic magnetic materials and organic magnetoelectric complexes, thus paving the way for the understanding of organic magnetism and magnetoelectric coupling mechanisms. In addition, this analysis provides us a critical guide for future organic magnetic material design and fabrication.

关键词： organic materials magnetism magnetoelectric coupling effect

SNORA23 inhibits HCC tumorigenesis by impairing the 2'-O-ribose methylation level of 28S rRNA

在线全文

学校读者我要写书评

暂无评论

Cancer Biology & Medicine 2022年第1期19卷 104-119页

作者： Zhiyong Liu Yanan Pang Yin Jia qin qin Rui Wang wei Li Jie jing Haidong Liu Shanrong Liu Department of Laboratory Diagnostics Changhai HospitalSecond Military Medical UniversityShanghai 200433China Department of Gastroenterology and Hepatology Zhongshan HospitalFudan UniversityShanghai 200032China Department of Gastroenterology Changhai HospitalSecond Military Medical UniversityShanghai 200433China Shanghai Institute of Pancreatic Diseases Shanghai 200433China Department of Chemistry and State Key Laboratory of Molecular Engineering of Polymers Fudan UniversityShanghai 200433 China Department of General Surgery Changzheng HospitalSecond Military Medical UniversityShanghai 200433China Shanghai Fourth People’s Hospital Tongji University School of MedicineShanghai 200081China

Objective:The dysregulation of ribosome biogenesis is associated with the progression of numerous tumors,including hepatocellular carcinoma(HCC).Small nucleolar RNAs(sno RNAs)regulate ribosome biogenesis by guiding the modification of ribosomal RNAs(r RNAs).However,the underlying mechanism of this process in HCC remains ***:RNA immunoprecipitation and sequencing were used to analyze RNAs targeted by ribosome *** biological functions of SNORA23 were examined in HCC cells and a xenograft mouse *** elucidate the underlying mechanisms,the 2′-O-ribose methylation level of r RNAs was evaluated by q PCR,and the key proteins in the PI3 K/Akt/m TOR pathway were detected using Western ***:Twelve sno RNAs were found to co-exist in 4 cancer cell lines using RPS6 pull-down ***23 was downregulated in HCC and correlated with the poor prognoses of HCC ***23 inhibited the proliferation,migration,and invasion of HCC cells both in vitro and in *** also found that SNORA23 regulated ribosome biogenesis by impairing 2′-O-ribose methylation of cytidine4506 of 28 S r ***,SNORA23,which is regulated by the PI3 K/Akt/m TOR signaling pathway,significantly inhibited the phosphorylation of 4 E binding protein ***23 and rapamycin blocked the PI3 K/AKT/m TOR signaling pathway and impaired HCC growth in ***:SNORA23 exhibited antitumor effects in HCC and together with rapamycin,provided a promising therapeutic strategy for HCC treatment.

关键词： SNORA23 ribosome biogenesis rRNA methylation HCC

Double glow plasma carburization on zirconium to improve surface hardness and wear resistance

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2017年第7期36卷 569-573页

作者： Jian-qing Wang Hong-Bo Yang Bing Zhang wei Xi Ze Dong qin jing State Key Laboratory o'f Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

Though some important progress in the excel- lent mechanical properties of zirconium alloys have been reported, their high surface hardness and good wear prop- erties need to be explored further. In this work, a carbur- ized layer was formed on the surface of commercially pure zirconium by a double glow plasma hydrogen-free car- burizing technique. Commercial high-purity graphite was used as the carbon source material. X-ray diffraction （XRD）, scanning electron microscopy （SEM）, energy dis- persive spectroscopy （EDS）, Vickers hardness test, friction and wear test were used to characterize the samples car- burized. The carburized layer could be clearly observed under a microscope. XRD patterns indicate that the zirco- nium carbide phase is formed in the carburized layer. The surface hardness of the sample increases significantly after carburization. Friction and wear tests results show that wear resistance and friction coefficient of zirconium are improved considerably after carburization. Surface plastic deformation is arrested to a low extent in contrast with pure zirconium because of the presence of ZrC phases during the wear test. The results may provide new insight into methods for surface strengthening of zirconium alloys.

关键词： Zirconium alloys Carburization Hardness Wear resistance

在线全文

学校读者我要写书评

暂无评论

甲状腺全切术治疗甲状腺多发结节的临床效果

中国当代医药 2021年第27期28卷 114-116页

作者：刘轩王斌郭春鹏常欣李孝彬秦为径解放军63750部队医院外一科陕西西安710043

目的探讨甲状腺全切术治疗甲状腺多发结节的临床效果。方法选取2018年1月至2019年12月本院收治的100例甲状腺多发结节患者作为研究对象,依据随机数字表法分为对照组与实验组,各50例。对照组采用甲状腺次全切术治疗方法,实验组采用甲状... 详细信息

目的探讨甲状腺全切术治疗甲状腺多发结节的临床效果。方法选取2018年1月至2019年12月本院收治的100例甲状腺多发结节患者作为研究对象,依据随机数字表法分为对照组与实验组,各50例。对照组采用甲状腺次全切术治疗方法,实验组采用甲状腺全切术治疗方法。比较两组的临床效果、手术情况、甲状腺功能[包括促甲状腺激素(TSH)、血清游离T_(4)(FT_(4))、游离T_(3)(FT_(3))]及不良反应情况。结果实验组的治疗总有效率高于对照组,差异有统计学意义(P<0.05);实验组的手术时间、拔管时间以及出院时间短于对照组,差异有统计学意义(P<0.05);实验组的术中出血量少于对照组,差异有统计学意义(P<0.05);实验组治疗后的TSH、FT_(4)及FT_(3)指标均低于对照组,差异有统计学意义(P<0.05);实验组的不良反应总发生率低于对照组,差异有统计学意义(P<0.05)。结论甲状腺多发结节实施甲状腺全切术治疗的效果显著,而且安全性高。

关键词：甲状腺多发结节甲状腺全切术疗效不良反应

Facile preparation of covalent organic frameworks@alginate composite beads for enhanced uranium(Ⅵ) adsorption

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2022年第4期41卷 1323-1331页

作者： Pan Duan Duo-Yu Lin wei-Ting Yang Xiao-jing Huang A-Hui Sun qin-He Pan Key Laboratory of Advanced Materials of Tropical Island Resources Ministry of EducationChemical Engineering and TechnologyHainan UniversityHaikou 570228China

Covalent organic frameworks(COFs) have broad application prospects in adsorption and ***,as COFs are generally in powder form,their superior performance at the laboratory scale is difficult to transfer into pilot-or industrial-scale ***,there is a strong and urgent need to structure COFs into monolithic ***,a facile strategy was developed to prepare COFs@alginate composite *** composite beads comprising different COFs including TpPa-1(2,4,6-triformylphloroglucinol(Tp) and p-phenylenediamine(Pa-1)as monomers),TpDb(Tp and 2,5-diaminobenzonitrile(Db)as monomers) and TpTt(Tp and 1,3,5-triazine-2,4,6-triamine(Tt) as monomers) with controlled COF loading and product size have been facilely achieved via this strategy,validating the applicability of this ***,the representative TpDb@alginate composite beads showed good adsorption performance of uranium(VI) in aqueous solution with high adsorption capacity(635 mg·g^(-1)),good interference immunity and *** work offers a practical approach for incorporation of COFs into polymer matrix,which can serve as potential adsorbents for radioactive wastewater treatment.

关键词： Covalent organic frameworks Alginate Composite beads Uranium Adsorption

Audio Retrieval Based on Manifold Ranking and Relevance Feedback

在线全文

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2015年第6期20卷 613-619页

作者： jing qin Xinyue Liu Hongfei Lin School of Computer Science and Technology Dalian University of Technology College of Information Engineering Dalian University

An audio information retrieval model based on Manifold Ranking(MR) is proposed, and ranking results are improved using a Relevance Feedback(RF) algorithm. Timbre components are employed as the model’s main feature. To compute timbre similarity, extracting the spectrum features for each frame is necessary; the large set of frames is clustered using a Gaussian Mixture Model(GMM) and expectation maximization. The typical spectra frame from GMM is drawn as data points, and MR assigns each data point a relative ranking score, which is treated as a distance instead of as traditional similarity metrics based on pair-wise distance. Furthermore, the MR algorithm can be easily generalized by adding positive and negative examples from the RF algorithm and improves the final result. Experimental results show that the proposed approach effectively improves the ranking capabilities of existing distance functions.

关键词： audio information retrieval manifold ranking relev

Enhanced thermoelectric properties of Zintl phase YbMg_(2)Bi1.98 through Bi site substitution with Sb

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2020年第24期59卷 189-194页

作者： jing Wang Muchun Guo Jianbo Zhu Dandan qin Fengkai Guo Qian Zhang wei Cai Jiehe Sui National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin150001China Department of Materials Science and Engineering Harbin Institute of TechnologyShenzhenShenzhen518055China

Benefiting from the unique"Phonon-Glass,Electron-Crystal"(PGEC)characteristic,Zintl phases have been considered as a kind of promising thermoelectric *** the typical AM2X2 compounds with the CaAl2Si2-type structure,YbMg_(2)Bi2 has shown competitive thermoelectric performance ***,the optimization of YbMg_(2)Bi2 compounds is primarily focused on the substitution on Yb or Mg ***,the Bi site is substituted by isoelectric Sb and the effect on the thermoelectric transport behavior is *** partial substitution reduces the carrier concentration and induces the lattice deformation caused by the different atomic radius and mass between Bi and Sb,further leading to the decreased power factor and thermal ***,the reduction extent of the thermal conductivity outperforms that of power ***,the Sb substitution successfully results in a better thermoelectric performance compared with that of the pristine YbMg_(2)***,the calculated energy conversion efficiency(a)of YbMg_(2)Bi1.88Sb0.1 which also possesses a relatively high output power density reaches the maximum value of 9.8% when Th=873 K,and Tc=300 K,*** work demonstrates that the idea of substitution on anionic site should be a new strategy to achieve better ZT values for AM2X2 compounds.

关键词： Zintl phase YbMg_(2)Bi2 Anionic substitution Thermoelectric properties

Corrosion Resistance of Superhydrophobic Mg(OH)_(2)/Calcium Myristate Composite Coating on Magnesium Alloy AZ31

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2021年第12期34卷 1618-1634页

作者： Zheng-Zheng Yin wei Zhao jing Xu Rong-Chang Zeng Feng-qin Wang Zhen-Lin Wang Corrosion Laboratory for Light Metals College of Materials Science and EngineeringShandong University of Science and TechnologyQingdao 266590China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan 430070China College of Materials Science and Engineering Chongqing University of TechnologyChongqing 400065China

Hydrophobic Mg(OH)_(2)/calcium myristate(Ca[CH3(CH2)12COO]_(2),CaMS)and Mg(OH)_(2)/magnesium myristate(Mg[CH3(CH2)12COO]2,MgMS)composite coatings were prepared on the alkali-treated AZ31 substrates via both electrodeposition and dipping *** morphologies,compositions,and constitutes of the coatings were investigated by using field-emission scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS),and Fourier transform infrared spectrometry(FTIR)together with X-ray diffractometer(XRD).Furthermore,electrochemical(polarization and impedance spectroscopy)and hydrogen evolution tests were applied to evaluate the corrosion *** wettability and adhesive strength of the composite coatings were characterized through water static contact angle(CA),sliding angle(SA),and nano-scratch *** indicated that the better super-hydrophobicity,corrosion resistance,and adhesion were achieved via an electrodeposited *** corrosion current density(icorr)and hydrogen evolution rate(HER)of the electrodeposited coating were three and one orders of magnitude smaller than the substrate,implying a significantly improved corrosion *** scenario was ascribed to the super-hydrophobicity of electrodeposited composite coating with a contact angle(CA)and slide angle(SA)of 159.2°±0.8°and 5.2°±0.8°,***,the dipped composite coating was adverse to the improvement of corrosion resistance and adhesion due to the dissolution of the underlying Mg(OH)_(2)layer and smooth surface with less organic fatty acid salt(MgMS)

关键词： Magnesium alloy Electrodeposition and dipping Super-hydrophobicity Corrosion resistance