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Journal of Iron and Steel Research International 2012年第10期19卷 64-73页

作者： g Subhash Chander g Madhusudhan Reddy A Venugopal rao Swarna Bharathi Institute of Science and Technology Khammam 507002APIndia Defense Metallurgical Research Laboratory Kanchanbagh 500058APIndia

Fundamental investigation of continuous drive friction welding of austenitic stainless steel (AISI 304) and low alloy steel (AISI 4140) is described. The emphasis is made on the influence of rotational speed on the microstructure and mechanical properties such as hardness, tensile strength, notch tensile strength and impact toughness of the dissimilar joints. Hardness profiles across the weld show the interface is harder than the respective parent metals. In general, maximum peak hardness is observed on the stainless steel side, while other peak hardness is on the low alloy steel side. A trough in hardness distribution in between the peaks is located on the low alloy steel side. Peak hardness on the stainless steel and low alloy steel side close to the interface increases with a decrease in rotational speed. All transverse tensile joints fractured on stainless steel side near the interface. Notch tensile strength and impact toughness increase with increase in rotational speed up to 1 500 r/min and decrease thereafter. The mechanism of influence of rotational speed for the observed trends is discussed in the torque, displacement characteristics, heat generation, microstructure, fractography and mechanical properties.

关键词： friction welding dissimilar metal joint austenitic stainless steel low alloy steel microstructure impact toughness tensile strength

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亚紫裸伞的生物学特性及驯化栽培

生物技术通报 2024年第4期40卷 264-270页

作者：饶永斌张君丽三明市农业农村局三明365000 西藏自治区农牧科学院蔬菜研究所拉萨850000

【目的】为实现西藏野生真菌资源的高效开发与利用,促进食药用真菌产业的发展。【方法】对采自西藏自治区林芝市波密县易贡乡的一株野生真菌进行分离纯化,依据形态学特征和ITS序列进行菌种鉴定,并对该菌株进行了生物学特性探究和驯化栽... 详细信息

【目的】为实现西藏野生真菌资源的高效开发与利用,促进食药用真菌产业的发展。【方法】对采自西藏自治区林芝市波密县易贡乡的一株野生真菌进行分离纯化,依据形态学特征和ITS序列进行菌种鉴定,并对该菌株进行了生物学特性探究和驯化栽培试验。【结果】结合形态学特征和ITS系统发育树结果将该菌株鉴定为亚紫裸伞gymnopilus subpurpuratus;生物学特性分析表明,亚紫裸伞菌丝生长最佳碳源为葡萄糖,最佳氮源为酵母粉,最适pH为6.0,最适温度为30℃;驯化结果表明,亚紫裸伞在以木屑为主要栽培料的培养基中的满袋时间为39 d,原基形成时间为18 d,出原基后经8 d达到采收期,单朵鲜重45.99 g。【结论】成功以木屑为主要栽培料获得亚紫裸伞的人工驯化子实体,增加了药用菌的人工驯化新种类。

关键词：亚紫裸伞鉴定生物学特性驯化栽培

微波辅助深共熔溶剂提取紫斑牡丹籽总黄酮的工艺优化及其抗氧化活性

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食品工业科技 2024年第5期45卷 161-168页

作者：陈思羽饶桂维王露桦盛颖霏浙江树人学院树兰国际医学院浙江杭州310015 浙江树人学院交叉科学研究院浙江杭州310015 浙江树人学院生物与环境工程学院浙江杭州310015

目的:优化紫斑牡丹籽总黄酮的微波辅助深共熔溶剂提取方法,并探究其体外抗氧化活性。方法:以低共熔溶剂作为提取溶剂,采用微波辅助技术提取紫斑牡丹籽中的总黄酮。采用单因素实验以及响应面法进行提取工艺优化。从DPPH自由基清除率、羟... 详细信息

目的:优化紫斑牡丹籽总黄酮的微波辅助深共熔溶剂提取方法,并探究其体外抗氧化活性。方法:以低共熔溶剂作为提取溶剂,采用微波辅助技术提取紫斑牡丹籽中的总黄酮。采用单因素实验以及响应面法进行提取工艺优化。从DPPH自由基清除率、羟基自由基清除率进行总黄酮的体外抗氧化活性研究。结果:以氯化胆碱作为氢键受体,脲作为氢键供体的低共熔溶剂体系下,在摩尔比为1:3,含水量41.80%(V/V)的深共熔溶剂体系最优,料液比1:19 g/mL,微波功率为110 W,微波时间3.00 min,此时紫斑牡丹籽总黄酮得率为1.76 mg/g。当提取物总黄酮浓度在80μg/mL时,对DPPH·、羟基自由基的清除率分别为82.00%、42.10%。结论:采用微波辅助深共熔溶剂提取紫斑牡丹籽总黄酮,含量高,均具有抗氧化活性,且对DPPH自由基清除率超80%。

关键词：紫斑牡丹籽黄酮深共熔溶剂微波辅助提取抗氧化

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Preparation and Characterization of Nano-Sized (Mg(x)Fe(1–x)O/SiO2) (x = 0.1) Core-Shell Nanoparticles by Chemical Precipitation Method

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Advances in Nanoparticles 2012年第3期1卷 37-43页

作者： Mohsen Ahmadipour Mozhgan Hatami Kalagadda venkateswara rao Center Nano science and Technology Institute of Science and Technology Jawaharlal Nehru Technological University Hyderabad Hyderabad India

Magnetic core-shell nanoparticles have been widely studied because of their excellent and convenient magnetic and electrical *** this present work core-shell magneticnanoparticles (MNPs) were synthesized by simple chemical precipitation method. Firstly Mg(x)Fe(1–x)O (magnesiwuestite) nano powder samples were synthesised by low temperature chemical combustion method. Secondly the as synthesised Mg(x)Fe(1–x)O nanoparticles are used to synthesis magnetic core-shell Nano particles byusing 2-propanol, poly ethylene glycol (PEg), ammonia solution 30 wt%, tetraethyl orthosilicate (TEOS). Separation of the core-shell magnetic nanoparticles from the aqueous suspension using a centrifuge. The synthesised MNPs and core shell MNP were characterized by X-ray diffraction (XRD), Thermal gravimetric-differential thermal analyzer (Tg-DTA), Transmission electron microscopy (TEM), scanning electron microscopy (SEM), (EDAX) for structural, thermal and morphological respectively. It is observed that the particle size of spherical sampleis 32.5 nm.

关键词： Magnetic Nanoparticle Core-Shell Tg-DTA SEM TEM

Method Development and Validation for Simultaneous Estimation of Montelukast Sodium and Desloratadine by RP-HPLC

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American Journal of Analytical Chemistry 2015年第8期6卷 651-658页

作者： Bonthu Mohan gandhi Atmakuri Lakshmana rao Jangala venkateswara rao Sri Vasavi Institute of Pharmaceutical Sciences Tadepalligudem India V. V. Institute of Pharmaceutical Sciences Gudlavalleru India Bharat Institute of Pharmacy Mangalpally India

A novel, precise, accurate, rapid and cost effective isocratic reverse-phase high performance liquid chromatographic (RP-HPLC) method was developed, optimized and validated for the simultaneous estimation of Montelukast Sodium (MON) and Desloratadine (DES) in pharmaceutical dosage forms. The drugs were estimated using Hypersil BDS C18 (250 mm × 4.6 mm I.D., 5 μ particle size) column. The mobile phase composed of orthophosphoric acid and water in the ratio of 20:80 v/v, at a flow rate of 1.0 ml/min was used for the separation. Detection was carried out at 280 nm. The linearity range obtained was 10 - 30 μg/ml for MON and 5 - 15 μg/ml for DES with retention times of 2.929 min and 4.439 min for MON and DES respectively. The correlation coefficient values were found to be 0.999. Precision studies showed % RSD values less than 2% for both the drugs in all the selected concentrations. The percentage recoveries of MON and DES were in the range of 99.59% - 99.82% and 99.60% - 99.80% respectively. The limit of detection (LOD) and limit of quantification (LOQ) were 0.176 μg/ml, 0.587 μg/ml for MON and 0.087 μg/ml, 0.292 μg/ml for DES respectively. The method was validated as per the International Conference on Harmonization (ICH) guidelines. The proposed validated method was successfully used for the quantitative analysis of commercially available tablet dosage forms.

关键词： Montelukast Sodium Desloratadine HPLC Validation

重组大肠杆菌S3-2产羰基还原酶发酵工艺优化及动力学研究

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化学与生物工程 2024年第5期41卷 25-30,43页

作者：田俊龚大春饶振辉三峡大学生物与制药学院湖北宜昌443002 三峡大学附属第二人民医院湖北宜昌443099 安琪酵母股份有限公司湖北宜昌443003

以重组大肠杆菌S3-2为发酵菌株,通过单因素实验和正交实验对重组大肠杆菌S3-2产羰基还原酶的1 L发酵罐发酵工艺进行优化,并通过Logistic方程和Luedeking-Piret方程对重组大肠杆菌S3-2分批发酵产羰基还原酶的动力学过程进行模拟。结果表... 详细信息

以重组大肠杆菌S3-2为发酵菌株,通过单因素实验和正交实验对重组大肠杆菌S3-2产羰基还原酶的1 L发酵罐发酵工艺进行优化,并通过Logistic方程和Luedeking-Piret方程对重组大肠杆菌S3-2分批发酵产羰基还原酶的动力学过程进行模拟。结果表明,重组大肠杆菌S3-2的最佳发酵工艺为:IPTg在OD600值为1.0时诱导、IPTg终浓度为0.30 mmol·L^(-1)、种子液OD600值为3.0时接种、诱导温度为26℃,在此条件下,菌体细胞干重为1.586 g·L^(-1)、羰基还原酶酶活为0.712 U·mL^(-1);菌体生长、羰基还原酶酶活及甘油消耗的动力学模型的拟合度分别为0.9883、0.9917和0.9807,说明该模型对重组大肠杆菌S3-2的发酵动力学模型拟合良好,为后续中试放大研究提供了理论依据。

关键词：重组大肠杆菌S3-2 羰基还原酶发酵工艺优化正交实验动力学模型

基于多DNN的5g双域专网模式的研究与应用

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长江信息通信 2024年第5期37卷 172-174页

作者：饶亮中国移动通信集团湖北有限公司网管中心湖北武汉430040

随着5g ToB网络的不断演进,基于ULCL(上行分流器)的双域专网越来越被市场特别是高校类客户所接受,其最大的亮点是数据不出园区,用户不用更换终端和手机卡便可以同时使用公网和内网,兼顾了内网数据保密性和使用公网的便捷性,但是目前大... 详细信息

随着5g ToB网络的不断演进,基于ULCL(上行分流器)的双域专网越来越被市场特别是高校类客户所接受,其最大的亮点是数据不出园区,用户不用更换终端和手机卡便可以同时使用公网和内网,兼顾了内网数据保密性和使用公网的便捷性,但是目前大部分的基于ULCL双域专网方案是基于单DNN的模式,漫游场景下时延较高,时延敏感型体验较差;核心网业务数据配置复杂。对此,文章介绍了一种基于多DNN的双域专网模式,进一步提升用户的感知,并通过实际案例验证了方案的可行性。

关键词： DNN ULCL 双域专网

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Analysis of Multi-Component Non-Stationary Signals Using Fourier-Bessel Series and Wigner-Hough Transform

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Journal of Electronic Science and Technology 2017年第1期15卷 69-76页

作者： g.Ravi Shankar Reddy Rameshwar rao Department of Electonics and Communication Engineering CVR College of EngineeringHyderabad 501510India Jawaharlal Nehru Technological University Hyderabad 500085India

We presented a novel Fourier-Bessel（FB）series and Wigner-Hough transform（WHT） method for the analysis of multi-component non-stationary *** FB series decomposed multi-component nonstationary signals into mono-component signals. The Wigner-Ville distribution（WVD） was applied to each mono-component signal to analyze its time-frequency distribution（TFD）. Summing up the WVDs of the individual components resulted in TFDs of the multicomponent signals, where the cross terms and noise were significantly reduced. The Hough transform（HT）was applied on the TFD of the multi-component signal（obtained from FB-WVD）. The HT provides an important tool for mapping the signals onto a parameter space where the detection and estimation problems are made easier. This mapping can be used in the detection and parameter estimation of signals which are unknown and embedded in noise.

关键词： decomposed Bessel Wigner stationary overlapping reconstructed chirp priori utilized drawback

基于5g双域专网的多场景自动拨测研究与应用

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长江信息通信 2024年第5期37卷 221-223页

作者：饶亮中国移动通信集团湖北有限公司网管中心湖北武汉430040

5g垂直行业2B网络智能运维是组成网络数智化转型的重要组成部分,为打通运维管理到市场支撑中间各个环节,提高5g双域专网的运维能力。对此,介绍了一种5g双域专网的多场景自动拨测模式,实现了5g ToC双域专网拨测异常检测能力,可以根据客... 详细信息

5g垂直行业2B网络智能运维是组成网络数智化转型的重要组成部分,为打通运维管理到市场支撑中间各个环节,提高5g双域专网的运维能力。对此,介绍了一种5g双域专网的多场景自动拨测模式,实现了5g ToC双域专网拨测异常检测能力,可以根据客户需求在5g toC双域专网业务质量监测、隐患挖掘、隐患预处理等多场景下使用,是支撑网络运维、前端市场的重要手段和工具。

关键词： 5g 双域专网自动拨测

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Fiber Loading of Date Palm and Kenaf Reinforced Epoxy Composites:Tensile,Impact and Morphological Properties

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Journal of Renewable Materials 2021年第7期9卷 1283-1292页

作者： Syed Waheedullah ghori g.Srinivasa rao Department of Mechanical Engineering Acharya Nagarjuna University-College of Engineering and TechnologyGunturAndhra PradeshIndia Department of Mechanical Engineering RVR&JC College of Engineering and TechnologyGunturAndhra PradeshIndia

Date palm fiber(DPF)and kenaf fiber were reinforced in epoxy having various fiber loading 40%,50%,and 60%by *** hybrid samples were manufactured by hot press technique and then characterized for tensile,impact,and morphological behavior to evaluate the ratio of fibers in the hybrid composites;the addition of kenaf improved the tensile properties,Scanning Electron Microscopy(SEM)revealed the interfacial bonding of fiber/matrix,and dispersion and void content in *** test studies reflected the effect of natural fiber with epoxy,level of stress transfer from matrix to reinforced material,and reinforced material’s role in absorbing the *** showed that 50%of DPF had the best shock-absorbing *** obtained results indicated that 30%DPF in hybrid composite showed improved tensile properties and homogeneous distribution of fiber without void content;however,50%DPF loading in hybrid composites had the best impact properties.

关键词： Date palm fibre kenaf fibre epoxy resin tensile properties impact strength and scan electron microscopy