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Structures and Properties of LiF Cluster-assembled Nanofilms

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Journal of Materials Science & Technology 1997年第4期13卷 274-279页

作者： Wang, GH liu, fq CTR ADV STUDIES & TECHNOL MICROSTRUCT NANJING 210093PEOPLES R CHINA

We have studied structures and properties of nanostructured films prepared with nanometer-sized lithium fluoride (Lif) clusters by inert gas condensation method, and then characterized by transmission electron microscope, Fourier transform infrared spectra and Raman scattering spectra, etc. Following important results are obtained: Multi-order-like Raman scatterings from LiF clusters are obtained, including the fine structure of the spectra. The observed Raman peaks are discussed in terms of surface optical modes, LO, TO, LA modes and their combination form. As the cluster size decreases, the phonons are confined in nanoscale so that the q vector selection rule is relaxed or even totally free of q conservation, and prohibition at the first- and third-order scatterings in the bulk LiF crystal is relaxed. The surface modes appear and play an important role in Raman scattering processes. The infrared absorption spectra are obtained with different deposition conditions. When the clusters are in the medium size range from similar to 7 to 15 nm, most infrared absorption peaks are second-order feature, and no single surface mode emerges. For the smaller clusters, molecular-like vibration is observed whereas the broad band of long wavelength transverse-optical modes appear from 580 to 400 nm(-1) for the clusters larger than 19 nm.

关键词： Nanostructured materials

Three New Classes of Subsystem Codes

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Wuhan University Journal of Natural Sciences 2024年第1期29卷 38-44页

作者： LI Hui liu Xiusheng HU Peng School of Mathematics and Physics Hubei Polytechnic UniversityHuangshi 435003HubeiChina College of Arts and Science Hubei Normal UniversityHuangshi 435003HubeiChina

In this paper,we construct three classes of Clifford subsystem maximum distance separable(MDS)codes based on Reed-Solomon codes and extended generalized Reed-Solomon codes over finite fields fq for specific code ***,o... 详细信息

关键词： Clifford subsystem codes Reed-Solomon codes generator matrices

番茄内生菌的分离鉴定及菌株fq-G3抗病促生特性

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微生物学报 2024年第1期64卷 208-219页

作者：冯宝珍李培谦刘缙杨燕丽王晓静运城学院生命科学系山西运城044000

由灰葡萄孢(Botrytis cinerea)引起的灰霉病是番茄生产中最重要的病害之一,当前使用的杀菌剂因药物残留、病原菌抗药性及食品安全等原因逐渐受到限制。因此,利用拮抗微生物的生物防治逐渐成为灰霉病防控的有效策略。【目的】从番茄植株... 详细信息

由灰葡萄孢(Botrytis cinerea)引起的灰霉病是番茄生产中最重要的病害之一,当前使用的杀菌剂因药物残留、病原菌抗药性及食品安全等原因逐渐受到限制。因此,利用拮抗微生物的生物防治逐渐成为灰霉病防控的有效策略。【目的】从番茄植株体内筛选具有抗病促生特性内生菌株并对其生防潜力进行评估,为开发番茄灰霉病生物防治新策略提供理论依据。【方法】采用组织分离法在番茄植株不同部位分离出内生细菌、真菌,结合16SrRNA和ITS序列分析,对候选菌株进行初步鉴定;通过菌株对峙培养、果实离体接种筛选对灰葡萄孢具有拮抗活性的内生菌;进一步测定菌株分泌生长素、嗜铁素的能力及其对拟南芥和番茄幼苗生长的促生特性。【结果】从番茄植株不同部位共分离出72株内生细菌和31株内生真菌,通过平板对峙法筛选出1株对多种病原菌具有较好抑菌活性的内生细菌fq-G3,分子鉴定为Bacillus velezensis。fq-G3对灰葡萄孢抑菌率达80.93%,并显著抑制灰葡萄孢在番茄果实上的扩展。该菌株能够分泌生长素、蛋白酶和嗜铁素,且对拟南芥、番茄幼苗具有明显的促生效果。【结论】本研究表明分离自番茄植株的内生菌fq-G3具有抗病促生特性,对番茄灰霉病的防控具有潜在应用价值。研究结果丰富了番茄内生菌资源,为番茄灰霉病的防病促生提供技术和理论支持。

关键词：灰霉病内生菌鉴定生物防治促生作用

Influence of peptide bond on photosensitized oxidation of tryptophan, tyrosine and histidine dipeptides

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Chinese Science Bulletin 1997年第19期42卷 1624-1628页

作者： liu, JB Zhang, FS Zhao, y Zhao, fq Tang, yW Song, XQ TSING HUA UNIV DEPT CHEMBEIJING 100084PEOPLES R CHINA

IN photodynamic therapy, the damage of protein results from the photooxidation of one ormore of only five amino acid residues (tryptophanyl, tyrosyl, histidyl, methionyl and cys-teinyl). These five amino acids are also readily photooxidized in their monomeric states. How-ever, the reaction kinetics and mechanisms of free amino acids and bound amino acid residuesin proteins are somewhat different. For example, Tassin found that the incorporation of tryp-tophan into a peptide linkage dramatically altered its susceptibility to photooxidation as well

关键词： amino acid dipeptide photosensitized oxidation.

Study of Origin of Shape Memory Effect for TiNi Alloy byPositron Annihilation

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Journal of Materials Science & Technology 1998年第4期14卷 368-370页

作者： Wang, JC you, fq Qi, JL Tang, XF Shanghai Iron & Steel Res Inst Shanghai Key Lab Met Funct Mat Shanghai 200940 Peoples R China Shanghai Iron & Steel Res Inst Res Ctr Shanghai 200940 Peoples R China Tongji Univ Dept Phys Shanghai 200092 Peoples R China

A number of specimens of Ti-51Ni (at. pet) alloy showing reversible shape memory effect (RSME) have been measured as to reversibility and S-lineshape parameter of positron annihilation. It is found that the Ti-51Ni specimens showing good memory effect contain structural defects. Not all specimens including structural defects (or structural imperfection) are able to exhibit good memory effect. The structural defects have to be appropriate in density, neither too much nor too little. With no or too much structural defects a good RSME could not take place. It is fully as important that the structural defects exist as it is for the structural defects to be appropriate in density in order to obtain a good RSME.

关键词： Titanium alloys

An Explanation on the Electron Ionization Mass Spectra of Crown Ethers by MNDO Computational Method

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Chemical Research in Chinese Universities 1995年第3期11卷 202-205页

作者： yUAN, HS TANG, MS WU, yJ TU, yP MA, fq ZHENGZHOU UNIV DEPT CHEMZHENGZHOU 450052PEOPLES R CHINA ZHENGZHOU UNIV CTR TESTZHENGZHOU 450052PEOPLES R CHINA

he bond lengths and bond orders of four kinds of chemical bonds in crownethers(15) were calculated based on the model molecules using MNDO *** the calculation results, some predictions to the EI mass spectral fragmenta-tion behaviour of crown ethers are suggested. The EI mass spectra of studied crownethers are in satisfactory agreenient with the predictions.

关键词： Crown ether MNDO method. EI mass spectra

SAT-TB联合fq-PCR检测在痰涂片阴性肺结核诊断中的效能

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中国民康医学 2024年第7期36卷 136-138页

作者：刘延华郏县人民医院医学检验科河南平顶山467100

目的:分析RNA恒温扩增实时检测技术(SAT-TB)联合荧光定量聚合酶链反应(fq-PCR)检测在痰涂片阴性肺结核患者诊断中的效能。方法:选取2020年7月至2022年7月该院收治的75例疑似痰涂片阴性肺结核患者进行前瞻性研究。采集所有患者肺泡灌洗... 详细信息

目的:分析RNA恒温扩增实时检测技术(SAT-TB)联合荧光定量聚合酶链反应(fq-PCR)检测在痰涂片阴性肺结核患者诊断中的效能。方法:选取2020年7月至2022年7月该院收治的75例疑似痰涂片阴性肺结核患者进行前瞻性研究。采集所有患者肺泡灌洗液标本,采用SAT-TB、fq-PCR法进行检测,以结核分枝杆菌痰培养结果为“金标准”,比较SAT-TB、fq-PCR单项及联合检测在痰涂片阴性肺结核诊断中的效能。结果:金标准结果显示,75例疑似痰涂片阴性肺结核患者中,阳性48例,阴性27例;SAT-TB检测结果显示,阳性36例,阴性39例;fq-PCR检测结果显示,阳性37例,阴性38例;SAT-TB联合fq-PCR检测结果显示,阳性47例,阴性28例;SAT-TB联合fq-PCR检测诊断痰涂片阴性肺结核的灵敏度、准确度均高于SAT-TB、fq-PCR单项检测诊断,漏诊率低于SAT-TB、fq-PCR单项检测诊断,差异有统计学意义(Pfq-PCR检测诊断痰涂片阴性肺结核的效能高于二者单项检测诊断效能。

关键词： RNA恒温扩增实时检测技术荧光定量PCR 痰涂片阴性肺结核准确度

Significant Carnian Halobia Fauna found in the Zagunao Formation in the Songpan area, Sichuan, China

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Chinese Science Bulletin 1997年第12期42卷 1056-1056页

作者： Wang, HM yang, fq Xie, SC jin, GB Geology Faculty China University of Ceosciences Wuhan China The Sixth Geology Survey Institute of Jilin Province Yanji China

NORTHWEST Sichuan, a hotspot for geologic study, recently has yielded a series of large-medi-um scale gold deposits in the Upper Triassic. It is of great importance to determination andsubdivision of the Triassic System and eventually to exact locating of the gold *** Triassic Zagunao Formation in northwestern Sichuan has greatly changed in sensesince it was named in 1961. Now the Zagunao Formation only includes the metamorphic sand-stone with interlayers of slate lying between the Zhuwo Formation （T3） and the Zagashan For-

关键词： Significant Carnian Halobia Fauna found in the Zagunao Formation in the Songpan area China Sichuan

添加不同形式屎肠球菌对凡纳对虾生长性能、非特异免疫及抗病力影响的比较研究

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中国海洋大学学报（自然科学版） 2024年第10期54卷 179-189页

作者：田相利刘云慧刘怡君汪仕爽罗凯刘杨秦光彩范瑞用海水养殖教育部重点实验室(中国海洋大学) 山东青岛266003 青岛瑞滋海洋工程研究院有限公司山东青岛266408

为了研究饲料中添加不同形式的屎肠球菌(Enterococcus faecium)LyB对凡纳对虾(Penaeus vannamei)生长、免疫及抗病力的影响。本研究设置了5种不同添加形式,分别为屎肠球菌发酵液(FJ)、活菌体(HJ)、发酵上清液(fq)、超声波破碎菌体(CS)... 详细信息

为了研究饲料中添加不同形式的屎肠球菌(Enterococcus faecium)LyB对凡纳对虾(Penaeus vannamei)生长、免疫及抗病力的影响。本研究设置了5种不同添加形式,分别为屎肠球菌发酵液(FJ)、活菌体(HJ)、发酵上清液(fq)、超声波破碎菌体(CS)和热灭活菌体(RM),以商品饲料作为对照(Con),实验周期为42 d。研究表明,各处理组对虾成活率在84.0%~96.0%之间,Con组成活率最高且与CS组差异不显著(P>0.05)。从对虾生长情况来看,HJ和CS组对虾末体质量和特定生长率显著高于fq、RM和Con组(P0.05)。各处理组对虾血清中的超氧化物歧化酶(SOD)、酚氧化酶(PO)、碱性磷酸酶(AKP)、酸性磷酸酶(ACP)、溶菌酶(LZM)活性以及总抗氧化能力(T-AOC)均显著高于Con组(Pfq组(Pfq和Con组,其中CS组的HSP70、LZM和proPO基因表达水平最高,各处理组对虾肝胰腺中Imd、Toll和Relish基因相对表达量显著高于Con组(Pfq和FJ组(P0.05)。在mTOR信号通路中,FJ、CS和RM组对虾肝胰脏TOR和4E-BP基因表达水平显著高于fq和Con组(Pfq和Con组(Pyticus)攻毒结果表明,CS组对虾累计死亡率显著低于对照组(PyB活菌菌液和超声波破碎菌体可显著提升其生长性能和免疫能力,其中超声波破碎菌体可作为潜在后生元,用于提高凡纳对虾的生长、免疫和抗病力。

关键词：屎肠球菌凡纳对虾饲料生长免疫抗病力后生元

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