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Immunogenicity and reactogenicity of a recombinant hepatitis B vaccine in subjects over age of forty years and response of a booster dose among nonresponders 被引量:12
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作者 Kunal Das R.K.Gupta +1 位作者 v.kumar P.Kar 《World Journal of Gastroenterology》 SCIE CAS CSCD 2003年第5期1132-1134,共3页
AIM:The study was initiated to evaluate the reactogenicity and immunogenicity of a recombinant hepatitis B vaccine in age group >40 years and to study the response of a single booster dose in primary non-responders... AIM:The study was initiated to evaluate the reactogenicity and immunogenicity of a recombinant hepatitis B vaccine in age group >40 years and to study the response of a single booster dose in primary non-responders to the hepatitis B vaccination. METHODS:A total of 102 volunteers without markers of hepatitis B infection (negative for HBsAg,anti-HBc antibody, HBeAg and anti-HBs antibody) received 20μg of recombinant HB vaccine intramuscularly at 0,1,and 6 months.Anti HBs titers were evaluated by a quantitative Elisa kit at 90 and 210 days.A booster dose of 20μg HB vaccine was given after 6 months of the 3^(rd) vaccine dose to the 15 non- responders and anti-HBs titers were measured after i month. RESULTS:Seroprotection (anti-HBs GMT^3 10 IU/L) was achieved in 85.3 % (87/102) volunteers.The mean GMT titers of the vaccine responders was 136.1 IU/L.Of the seroprotected individuals,there were 32.4% (33/102) hyporesponders (anti- HBs titers <10-99 mIU/ml) and 52.9% (54/102) were responders (anti-HBs titers >100 IU/L).All the non-responders (15/15) responded to a single dose of the booster dose of recombinant HB vaccine and their mean anti-HBs antibody titers were more than 100.5 mIU/ml after the booster dose. CONCLUSION:Recombinant hepatitis B vaccine offers good seroprotection in the age group >40 years and has a good safety profile.A single booster dose after 6 months in primary non-responders leads to good seroprotective anti-HBs antibody titers.However,larger population based studies are needed to evaluate the role of a booster dose in selected group of non-responders and whether such an approach will be cost effective. 展开更多
关键词 Adult Age Factors Aged Female Hepatitis B Antibodies Hepatitis B Vaccines DOSAGE Humans Immunization Secondary Male Middle Aged Safety Vaccines Synthetic
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纺织品过滤材料及其应用 被引量:8
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作者 v.kumar 张威 《国外纺织技术(纺织针织服装化纤染整)》 2004年第1期34-40,共7页
关键词 纺织品 过滤材料 过滤介质 过滤效率 织物设计 非织造物 机织物 纤维选择
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每核子14.6和60GeV能量下氧离子诱发核反应的带电粒子谱
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作者 M.I.Adamovich M.M.A■■arwal +82 位作者 R.Arora Y.A.Alexandrov S.A.Azimov S.K.Badyal E.Basova K.B.Bhalla A.Bhasin v.S.Badyal R.A.Bomadarenko T.H.Burnett 蔡(冒力) L.P.Chernova M.M.Chernyavski B.Dressel E.M.Friedlander S.I.Gerassimov E.R.Ganssau■e S.Garpman S.G.Gerassimov A.Gill J.Grote K.G.Gulamov v.G.Gulyamov v.K.Gupta S.Hackel H.H.Heckman B.Jakobsson B.Judek S.Katroo F.G.Kadyrov H.Kallies L.Karlsson G.L.Kaul M.Kaur S.P.Kharlamov J.Kohli v.kumar P.Lal v.G.Larinova P.J.Lindstrom 刘连寿 S.Lokanathan J.Lord N.S.Lukicheva L.K.Man■otra N.v.Maslennikova I.S.Mitta E.Monnand S.Moolerjee C.Mueller S.H.Nasyrov v.S.Nvtny G.I.Orlova I.Otterlund N.G.Peresadko S.Persson N.v.Petrov 钱琬燕 R.Raniwala S.Raniwana N.K.Rao J.Y.Rhee N.Shaidkhanov N.G.Salmanova W.Schulz F.Schussler v.S.Shukla D.Skeldin■ K.Soderstrom E.Stanlund R.S.Storey 孙君芬 L.N.Svechnilova M.I.Tretyakova T.P.Trofimova 王海桥 翁智群 R.J.Wilkes 许国发 张东海 郑蒲英 周代翠 周景晨 《高能物理与核物理》 CSCD 北大核心 1989年第10期865-869,共5页
本文给出了每核子14.6和60GeV能量下氧离子诱发核反应的带电粒子多重数分布和赝快度分布.实验数据取自EMU-01乳胶叠,并与Lund Monte Carlo模型(FRITIOF)作了比较.
关键词 氧离子 诱发 核反应 带电粒子谱
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DNA测序、PCR-SSCP和phaB间接药敏实验检测结核分枝杆菌利福平耐药性的比较 被引量:2
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作者 C.Mani N.Selvakumar +3 位作者 v.kumar S.Narayanan P.R.Narayanan 李传友 《国际结核病与肺部疾病杂志》 2003年第4期125-132,共8页
地点:印度Chennai结核病研究中心。目的:利用表型和基因型方法快速鉴定耐多药结核分枝杆菌。设计:对两种基因型分析方法,即 DNA测序法和聚合酶链反应-单链构象多态性(PCR-SSCP)法和一种表型分析方法,即噬菌体生物增殖法(phaB)进行了实... 地点:印度Chennai结核病研究中心。目的:利用表型和基因型方法快速鉴定耐多药结核分枝杆菌。设计:对两种基因型分析方法,即 DNA测序法和聚合酶链反应-单链构象多态性(PCR-SSCP)法和一种表型分析方法,即噬菌体生物增殖法(phaB)进行了实验室内的标准化,并利用这三种方法测定101株RFPr和100株RFPs临床分离结核分枝杆菌 的利福平耐药性。结果和结论:将三种方法的检测结果与常规间接药敏实验进行比较。DNA测序法的灵敏度和特异度分别为97%和100%,PCR-SSCP法为76%和100%,而phaB实验为97%和84%。DNA测序法的灵敏度和特异度高于其它两种方法。 展开更多
关键词 结核分枝杆菌 利福平耐药性 DNA测序 PCR-SSCP PhaB实验
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艾斯能对治疗合并有血管危险因素阿尔茨海默病患者的有效性和安全性研究(译文)(续) 被引量:1
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作者 v.kumar R.Anand +3 位作者 J.Messina R.Hartman J.veach 张振馨 《中国神经免疫学和神经病学杂志》 CAS 2001年第4期249-251,共3页
关键词 艾斯能 治疗 阿尔茨海默病 有效性 安全性
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Genotype × environmental interactions for analyzing adaptability and stability in different clones of Dalbergia sissoo Roxb.
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作者 A.kumar A.Bhatt +2 位作者 S.Ravichandran v.kumar S.Dobhal 《Journal of Forestry Research》 CAS CSCD 2012年第1期65-74,共10页
In total 36 superior clones of Dalbergia sissoo Roxb., screened from 300 selections conducted in natural and growing range of India and Nepal, were multiplied using single nodal cuttings and estab- lished to evaluate ... In total 36 superior clones of Dalbergia sissoo Roxb., screened from 300 selections conducted in natural and growing range of India and Nepal, were multiplied using single nodal cuttings and estab- lished to evaluate genotypexenvironmental interactions for adaptability and stability at the age of 30 months in three geographical locations in the state of Punjab, India. Clone 124 had maximum adaptability and stability (bi = 1.04) to perform exceedingly well over the locations. Clones 36 and 1 were stable with mean regression coefficient of 0.84 and 1.22, respectively. Nonetheless, clone 4 1 performed exceedingly well for all the characters to attain maximum population mean, and the perform- ance varied substantially across the locations. Therefore, clone 41 was considered as productive but non-adaptive clone. Though some of the clones were sensitive to sites, 14 clones for height, 16 for collar diameter, 12 for DBH and 7 for volume were relatively un-sensitive with higher regression coefficient. Nonetheless, clone 124 was the most Stable with average bi value of 1.04 and productive, which could play an important role in future breeding and commercial deployment of stable and produc- tive planting stock of Dalbergia sissoo. 展开更多
关键词 Dalbergia sissoo Roxb. GxE interactions stability parame-ters ADAPTABILITY superior genotypes
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Energy-Efficient Cluster in Wireless Sensor Network Using Life Time Delay Clustering Algorithms
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作者 v.kumar N.Jayapandian P.Balasubramanie 《Computer Systems Science & Engineering》 SCIE EI 2022年第10期77-86,共10页
Through Wireless Sensor Networks(WSN)formation,industrial and academic communities have seen remarkable development in recent decades.One of the most common techniques to derive the best out of wireless sensor network... Through Wireless Sensor Networks(WSN)formation,industrial and academic communities have seen remarkable development in recent decades.One of the most common techniques to derive the best out of wireless sensor networks is to upgrade the operating group.The most important problem is the arrangement of optimal number of sensor nodes as clusters to discuss clustering method.In this method,new client nodes and dynamic methods are used to determine the optimal number of clusters and cluster heads which are to be better organized and proposed to classify each round.Parameters of effective energy use and the ability to decide the best method of attachments are included.The Problem coverage find change ability network route due to which traffic and delays keep the performance to be very high.A newer version of Gravity Analysis Algorithm(GAA)is used to solve this problem.This proposed new approach GAA is introduced to improve network lifetime,increase system energy efficiency and end delay performance.Simulation results show that modified GAA performance is better than other networks and it has more advanced Life Time Delay Clustering Algorithms-LTDCA protocols.The proposed method provides a set of data collection and increased throughput in wireless sensor networks. 展开更多
关键词 WSNS Gravity analysis algorithm-GAA life time delay clustering algorithms-LTDCA end to end delay energy efficient
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Local perceptions of grassland change and priorities for conservation of natural resources of Banni, Gujarat, India
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作者 P.N.JOSHI v.kumar +2 位作者 M.KOLADIYA Y.S.PATEL T.KARTHIK 《Frontiers in Biology》 CSCD 2009年第4期549-556,共8页
This study was conducted in the Banni region of the Gujarat State,India,which is located in the western-most end of the country.The main objective was to investigate the local perceptions of grassland change,regenerat... This study was conducted in the Banni region of the Gujarat State,India,which is located in the western-most end of the country.The main objective was to investigate the local perceptions of grassland change,regeneration potentiality,socio-economic status and fac-tors that cause degradation of the vegetation resources in Banni.Participatory Rural Appraisal(PRA)was employed to generate the socio-economic profile of interviewed villages or hamlets.Information on vegetation deteriora-tion and changes in species composition significant for sustainable management of grassland was obtained through interviews with 51 elderly maldharies(pastoral-ists)and local inhabitants living in 31 villages in Banni.Local people had observed a change in the local surrounding habitats from grassland to woodland(domi-nated by Prosopis juliflora,locally called Gando Bavar)during their lifetime and considered it primarily a result of frequent intensive drought,constructed dams on flooding rivers in Banni,and declining rainfall.The socio-economic survey showed that the Banni communities are highly dependent on the natural grassland for various purposes.In particular,nine woody species were useful for construction of the traditional house called Bhunga,four for medicine and 22 for livestock fodder.Highly preferred and declining species were characteristically large wild thorny trees with edible fruits,viz.Acacia nilotica subsp.indica(Bavar),Prosopis cineraria(Kandho),and Salvadora persica(Kharijar).Some of the locally highly preferred grass species were also considered to be declining in the local environs;they included Dichanthium annulatum(Jinjvo),Cenchrus ciliaris(Dhaman),Sporobolus fertilis(Khevai)and Chloris barbata(Siyarpuchha).The study furthermore identified a close coincidence between the interest in conserving tree species diversity nearby the natural water resources and priorities of local inhabitants,which included protection of plenty of large trees(including many fruit tress,viz.Mangifera indicia(Ambo),Cordia dichotoma(Gunda)a 展开更多
关键词 INDIA KACHCHH pastoralist GRASSLAND arid areas CONSERVATION natural resource OVERGRAZING
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石墨烯纳米晶片对提高CNT-CB填充聚(1,4-顺式-异戊二烯)基纳米复合材料性能的作用
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作者 朱永康(编译) v.kumar +1 位作者 T.hanel H.K.Chougule 《现代橡胶技术》 2020年第3期38-44,共7页
研究了市售碳同素异形体和顺式1,4-聚异戊二烯(IR,又称“异戊二烯橡胶”)基纳米复合材料。所用的碳同素异形体为剥离型石墨烯纳米晶片xg C750(xGnPs)、碳纳米管(CNT-NC7000)和炭黑(CB-Printex xe2)。首先用炭黑和CNT与IR混炼制备CB-CNT... 研究了市售碳同素异形体和顺式1,4-聚异戊二烯(IR,又称“异戊二烯橡胶”)基纳米复合材料。所用的碳同素异形体为剥离型石墨烯纳米晶片xg C750(xGnPs)、碳纳米管(CNT-NC7000)和炭黑(CB-Printex xe2)。首先用炭黑和CNT与IR混炼制备CB-CNT基母炼胶。通过添加2~15质量份xg C750获得了终炼纳米复合材料。介绍了在橡胶基质中增加xg C750填充量对填充胶动态力学性能、热性能和电性能的作用。通过多次滞后损失试验证实了填料网络化的稳定性。 展开更多
关键词 纳米填料 石墨烯纳米晶片 橡胶纳米复合材料 混合填料
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利用微波遥感估算盐度
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作者 R.P.Singh v.kumar +1 位作者 S.K.Srivastav 吴隆业 《海岸工程》 北大核心 1996年第3期64-69,共6页
土壤水分的相互作用和释放出的离子引起水的盐度。河、湖、海洋和地表水,由于渗透作用和表面耗失而变化。我们通过数值计算的方法对代表河、湖和海洋水特征的各种模的微波响应进行了分析,研究了用微波遥感估算盐度的可行性。结果表明... 土壤水分的相互作用和释放出的离子引起水的盐度。河、湖、海洋和地表水,由于渗透作用和表面耗失而变化。我们通过数值计算的方法对代表河、湖和海洋水特征的各种模的微波响应进行了分析,研究了用微波遥感估算盐度的可行性。结果表明微波遥感响应特性对盐度和水表温度的依赖关系。研究结果对微波传感器参数的选择以及在微波遥感数据精确估算盐度方面是有用的。 展开更多
关键词 海洋水文学 海洋水 盐度 微波 遥感 估算
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Response of C_(2)H_(2)F_(4)superheated emulsion to quasi-mono-energetic neutrons at low frequency
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作者 v.kumar M.Das +5 位作者 S.Ali N.Biswas R.Shil K.Banerjee P.Pallav M.Nandy 《Radiation Detection Technology and Methods》 CSCD 2024年第2期1202-1207,共6页
Background The response of superheated emulsion detector with different halocarbons as active liquid to poly-energetic and mono-energetic neutrons has been carried out by different workers.The C_(2)H_(2)F_(4)detectors... Background The response of superheated emulsion detector with different halocarbons as active liquid to poly-energetic and mono-energetic neutrons has been carried out by different workers.The C_(2)H_(2)F_(4)detectors have not been explored much.This liquid has shown the potentiality of sensitivity to low-mass dark matter.The previous calibration of this liquid was carried out with the poly-energetic neutrons.Purpose In the present work,to better characterize the detector with neutrons,it is irradiated with quasi-mono-energetic neutrons and the results are compared with neutrons from 241Am-Be.To run the detector for the dark matter search,it is required to calibrate it with neutrons,preferably with mono-energetic neutrons.But mono-energetic neutron is not available at all establishments;hence,it was calibrated with quasi-mono-energetic neutrons.Method The response of superheated emulsion consisting of the droplets of C_(2)H_(2)F_(4)has been studied using the quasi-mono-energetic neutrons.The superheated droplets have been fabricated in a visco-elastic gel matrix.The shock waves generated by the passage of the energetic particles are detected by the acoustic sensors coupled to the emulsion.The measurement has also been carried out for the blank target and beam-off conditions.Results and conclusion It is observed that the(Pvar)response of the emulsion in the low-frequency range is sharper for the quasi-mono-energetic neutrons from 7Li(p,n)reaction and wider for the poly-energetic neutrons from 241Am-Be.The fundamental frequency associated with bubble nucleation(FF values)is similar for the neutrons from 7Li-target and 241Am-Be source.The precise characterization of such detector is required for the application in neutron measurement as well as for the dark matter search experiment apart from the basic understanding of the radiation-induced bubble nucleation. 展开更多
关键词 Superheated emulsion Bubble nucleation-Low frequency Quasi-mono-energetic Neutrons
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Relationship between Nutritional Support and Tuberculosis Treatment Outcomes in West Bengal, India 被引量:2
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作者 Blesson Samue Tyson volkmann +9 位作者 Sushma Cornelius Sugata Mukhopadhay MejoJose Kaushik Mitra Ajay M. v. kumar John E. Oeltmann Sidhajyoti Parija Aslesh Ottapura Prabhakaran Patrick K. Moonan vineet K. Chadha 《Journal of Tuberculosis Research》 2016年第4期213-219,共8页
Introduction: Poverty and poor nutrition are associated with the risk of developing tuberculosis (TB). Socioeconomic factors may interfere with anti-tuberculosis treatment compliance and its outcome. We examined wheth... Introduction: Poverty and poor nutrition are associated with the risk of developing tuberculosis (TB). Socioeconomic factors may interfere with anti-tuberculosis treatment compliance and its outcome. We examined whether providing nutritional support (monthly supply of rice and lentil beans) to TB patients who live below the poverty line was associated with TB treatment outcome. Methods: This was a retrospective cohort study of sputum smear-positive pulmonary TB patients living below the poverty line (income of <$1.25 per day) registered for anti-tuberculosis treatment in two rural districts of West Bengal, India during 2012 to 2013. We compared treatment outcomes among patients who received nutritional support with those who did not. A log-binomial regression model was used to assess the relation between nutritional support and unsuccessful treatment outcome (loss-to-follow-up, treatment failure and death). Results: Of 173 TB patients provided nutritional support, 15 (9%) had unsuccessful treatment outcomes, while 84 (21%) of the 400 not provided nutrition support had unsuccessful treatment outcomes (p < 0.001). After adjusting for age, sex and previous treatment, those who received nutritional support had a 50% reduced risk of unsuccessful treatment outcome than those who did not receive nutritional support (Relative Risk: 0.51;95% Confidence Intervals: 0.30 - 0.86). Conclusion: Under programmatic conditions, monthly rations of rice and lentils were associated with lower risk of unsuccessful treatment outcome among impoverished TB patients. Given the relatively small financial commitment needed per patient ($10 per patient per month), the national TB programme should consider scaling up nutritional support among TB patients living below the poverty line. 展开更多
关键词 Nutritional Support POVERTY Pulmonary Tuberculosis INDIA
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Effect of hydrogen plasma treatment on the growth and microstructures of multiwalled carbon nanotubes 被引量:1
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作者 S.K.Srivastava v.D.vankar v.kumar 《Nano-Micro Letters》 SCIE EI CAS 2010年第1期42-48,共7页
The effect of hydrogen plasma treatment of iron oxide films on the growth and microstructure of carbon nanotubes(CNTs)by microwave plasma enhanced chemical vapor deposition process has been investigated.Microwave plas... The effect of hydrogen plasma treatment of iron oxide films on the growth and microstructure of carbon nanotubes(CNTs)by microwave plasma enhanced chemical vapor deposition process has been investigated.Microwave plasma was characterized in-situ using optical emission spectrometer.Morphology of the films was examined by scanning electron microscopy.Structural analysis was carried out by high resolution transmission electron microscopy(HRTEM)equipped with energy dispersive X-ray spectroscopy(EDS)and micro-diffraction attachments.It is found that oxide films without H_2 plasma pretreatment or treated for lesser time resulted in CNT films with high percentage of carbonaceous particles and with embedded particles/nanorods distributed discontinuously in the cavity of the nanotubes.The embedded particles were found to be of iron carbide(Fe-C)as confirmed by HRTEM,EDS and micro-diffraction analysis.Experimental observations suggested that the iron oxide particles had poor catalytic action for CNT growth and in-situ reduction of oxide clusters to Fe by hydrogen plasma plays a key role in discontinuous filling of the nanotubes by the catalytic particles. 展开更多
关键词 Carbon nanotubes Chemical vapor deposition Iron carbide MPECVD
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Can Intensified Tuberculosis Case Finding Efforts at Nutrition Rehabilitation Centers Lead to Pediatric Case Detection in Bihar, India?
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作者 Rajeev R. Pathak Bal Krishna Mishra +5 位作者 Patrick K. Moonan Sreenivas A. Nair Ajay M. v. kumar Mohit P. Gandhi Shamim Mannan Smita Ghosh 《Journal of Tuberculosis Research》 2016年第1期46-54,共9页
Introduction: Seven district-level Nutritional Rehabilitation Centres (NRCs) in Bihar, India provide clinical and nutritional care for children with severe acute malnutrition (SAM). Aim: To assess whether intensified ... Introduction: Seven district-level Nutritional Rehabilitation Centres (NRCs) in Bihar, India provide clinical and nutritional care for children with severe acute malnutrition (SAM). Aim: To assess whether intensified case finding (ICF) strategies at NRCs can lead to pediatric case detection among SAM children and link them to TB treatment under the Revised National Tuberculosis Control Programme (RNTCP). Materials and Methods: A retrospective cohort study was conducted that included medical record reviews of SAM children registered for TB screening and RNTCP care during July-December 2012. Results: Among 440 SAM children screened, 39 (8.8%) were diagnosed with TB. Among these, 34 (87%) initiated TB treatment and 18 (53%) were registered with the RNTCP. Of 16 children not registered under the RNTCP, nine (56%) weighed below six kilo-grams—the current weight requirement for receiving drugs under RNTCP. Conclusion: ICF approaches are feasible at NRCs;however, screening for TB entails diagnostic challenges, especially among SAM children. However, only half of the children diagnosed with TB were treated by the RNTCP. More effort is needed to link this vulnerable population to TB services in addition to introducing child-friendly drug formulations for covering children weighing less than six kilo-grams. 展开更多
关键词 TUBERCULOSIS Children MALNUTRITION INDIA Screening
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Passwords Management via Split-Key
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作者 Kenneth Giuliani v. kumar Murty Guangwu Xu 《Journal of Information Security》 2016年第3期206-214,共9页
This paper proposes a scheme for password management by storing password encryptions on a server. The method involves having the encryption key split into a share for the user and one for the server. The user’s share... This paper proposes a scheme for password management by storing password encryptions on a server. The method involves having the encryption key split into a share for the user and one for the server. The user’s share shall be based solely on a selected passphrase. The server’s share shall be generated from the user’s share and the encryption key. The security and trust are achieved by performing both encryption and decryption on the client side. We also address the issue of countering dictionary attack by providing a further enhancement of the scheme. 展开更多
关键词 Password Encryption Password Storage Identity Management Secret Sharing
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木豆杂交组合主要性状的分析与评价
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作者 罗高玲 K.B.Saxena +1 位作者 R.v.kumar 杨示英 《中国种业》 北大核心 2006年第9期48-50,共3页
分析比较木豆杂交组合的部分农艺性状、叶特性和产量性状,并对开花期部分农艺性状、叶特性及产量性状进行相关性分析,结果表明,大部分组合在不同生育期的株高、叶面积、叶柄长、叶鲜重和叶干重均高于对照,株高较对照优势最大达44.16%。... 分析比较木豆杂交组合的部分农艺性状、叶特性和产量性状,并对开花期部分农艺性状、叶特性及产量性状进行相关性分析,结果表明,大部分组合在不同生育期的株高、叶面积、叶柄长、叶鲜重和叶干重均高于对照,株高较对照优势最大达44.16%。各组合单株荚数变化在104~165荚之间,对照优势最高可达108.86%。组合ICPH2438和ICPH2363的单株荚重、单株粒重及子粒产量等指标均高于对照品种,ICPH2438产量对照优势达34.14%。 展开更多
关键词 木豆 杂交组合 性状 分析评价
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Beneficiation of an Indian non-coking coal by column flotation 被引量:5
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作者 N. vasumathi T. v. vijaya kumar +3 位作者 S. Ratchambigai S. Subba Rao S. Prabhakar G. Bhaskar Raju 《International Journal of Coal Science & Technology》 EI 2016年第2期206-214,共9页
Beneficiation of non-coking coal is gaining ground in India. It not only reduces the volume of inert content to be transported to the power plant and also lowers the wear in the boiler houses. For special applications... Beneficiation of non-coking coal is gaining ground in India. It not only reduces the volume of inert content to be transported to the power plant and also lowers the wear in the boiler houses. For special applications such as the fuel for integrated gasification combined cycle plant (IGCC), the ash content in the coal should preferably be below 15 %. Indian coals are characterized by high inter-grown ash content mainly due to 'drift origin' of Gondwana formation in Permian age. This warrants fine grinding of non-coking coal in order to liberate the ash forming minerals from coal macerals. A non- coking coal sample of vitrinite type from India was ground to 44 ~tm (dso) and subjected to column flotation to improve its quality. The non-coking coal analyzing 34.6 % ash, 26.2 % volatile matter, 1.3 % moisture and 37.9 % fixed carbon could be upgraded to a concentrate/froth of 14.83 % ash at 72.18 % yield by optimizing collector and frother dosages and flotation column operating parameters, namely, froth depth, superficial feed velocity and superficial air velocity. The concentrate produced by this process is suitable as fuel for IGCC in coal-to-electricity route. 展开更多
关键词 Non-coking coal WASHABILITY BENEFICIATION Column flotation Coal gasification
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Influence of Machining Parameter on Tool Life While Machining Hybrid Metal Matrix Composites 被引量:1
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作者 C. R. Prakash Rao v. Ravi kumar +3 位作者 D. v. Ravi kumar Poorna Chandra M. vedavyasa M. S. Rajagopal 《Journal of Minerals and Materials Characterization and Engineering》 2020年第6期440-458,共19页
<span style="font-family:Verdana;">A metal matrix composite constitutes a continuous metallic matrix and a </span><span style="font-family:Verdana;">discontinuous phase known as r... <span style="font-family:Verdana;">A metal matrix composite constitutes a continuous metallic matrix and a </span><span style="font-family:Verdana;">discontinuous phase known as reinforcement. The hybrid metal matrix composites</span><span style="font-family:Verdana;"> (Hmmcs) have been used to manufacture drive shafts, disc brake rotors, brake drums, connecting rods pistons, engine block cylinder liners for automotive and rail vehicle applications. The Hmmcs castings of diameter 120 mm and length 300 mm were prepared through sand mould technique following stir casting methodology. The cast components further subjected to evaluation of physical properties and machining tests using two grades of coated inserts and PCD inserts. The experiments were carried out following ISO 3685 standards. The coating thickness of the TiN coated and TiAlN coated inserts were measured using Kalo testing method</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">;</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> the results of the test show that the interface of the substrate and coating was free from the porosity, and the coating thickness of TiN coating was 4.84 microns and TiAlN coating was measured 4.6 microns. The results of the experiments show that performance of the PCD insert was better than coated inserts at 0.1 mm/rev feed</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">;</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> however at 0.2 mm/revolution feed PCD insert failed by micro chipping of cutting edge while machining Hmmcs. When TiAlN coated inserts were us 展开更多
关键词 COMPOSITES Hybrid Metal Matrix Composites Coated Inserts PCD Inserts TURNING Tool Life Testing
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Fabrication, Characterization and Machining of Al6061 Reinforced with Red Mud Composite
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作者 Poorna Chandra v. Ravi kumar +3 位作者 R. Kiran D. v. Ravi kumar C. R. Prakash Rao R. Suresh 《Journal of Minerals and Materials Characterization and Engineering》 2022年第1期28-42,共15页
The Metal Matrix Composites application has increased in many areas of science and technology, because of its additional physical, wear and mechanical properties. In comparison with all MMC’s, aluminum-based MMC’s a... The Metal Matrix Composites application has increased in many areas of science and technology, because of its additional physical, wear and mechanical properties. In comparison with all MMC’s, aluminum-based MMC’s are finding wide applications due to their better strength to weight ratio, better stiffness, and high thermal conductivity as well as very good wear and corrosion properties. The properties of a composite mainly depend on better distribution of reinforcement in the matrix, which is very difficult to achieve. Basically Redmud is a byproduct of alumina, and it is waste product obtained during Bayer’s process. This waste product must be recycled else it may be dangerous to the environment. Redmud can be used as reinforcement for aluminium composites in order to achieve better properties. The proposed research work includes preparation of Aluminum 6061-Red mud metal matrix composites using liquid metallurgy route following stir casting technique. An alloy Al6061 containing 0.60 percent silicon and Magnesium of 0.82 percent was used as the matrix material. Two different compositions of the Aluminum 6061-Red mud composites are prepared in addition to the base matrix and evaluated for mechanical properties also the force acting on the cutting tool at different spindle speeds during machining of the composite materials were analyzed. 展开更多
关键词 Al6061 Redmud MACHINING MMC’s Cutting Force Measurement
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Phenotypic, Stress Tolerance and Plant Growth Promoting Characteristics of Rhizobial Isolates from Selected Wild Legumes of Semiarid Region, Tirupati, India 被引量:1
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作者 Y. Bhargava J. S. R. Murthy +1 位作者 T. v. Rajesh kumar M. Narayana Rao 《Advances in Microbiology》 2016年第1期1-12,共12页
Rhizobia are vital for nitrogen input, fertility of soil and legume plant growth. Knowledge on rhizobial diversity from arid and semiarid areas is important for dry land agriculture in the context of climatic change a... Rhizobia are vital for nitrogen input, fertility of soil and legume plant growth. Knowledge on rhizobial diversity from arid and semiarid areas is important for dry land agriculture in the context of climatic change and for economic utilization. This study provides morphological, biochemical, stress tolerance and plant growth promoting characteristics of fifteen rhizobial isolates from the nodules of same number of wild legumes and one isolate from cultivated Arachis hypogea from semi-arid region, Tirupati. The bacterial isolates were confirmed as rhizobia based on colony morphology and biochemical tests. Based on the colour change of YMA-BTB medium, eight isolates were identified as slow growers and six were fast growers. The isolates differed in growth pattern, colony morphology, antibiotic resistance at higher concentrations and uniformity in utilization of carbon and nitrogen sources. The isolates are tolerant to NaCl up to one percent, displayed normal growth at temperatures 28℃ - 30℃, at neutral pH and poor growth at pH 5and 9. The isolates varied in the production of EPS and IAA, positive for phosphate solubilization and siderophore formation. This functional diversity displayed by the isolates can be utilised for the legume crop production by cross inoculation. 展开更多
关键词 Wild Legumes Rhizobia Characterization Stress Tolerance Plant Growth Promotion
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