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Hydroesterification of Nannochloropsis oculatamicroalga’s biomass to biodiesel on Al2O3supported Nb2O5catalyst

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Natural Science 2012年第4期4卷 204-210页

作者： Angel Almarales Gisel Chenard roberto Abdala Donato A. Gomes Yordanka reyes Neyda om Tapanes Ecology Department University of Málaga Málaga Spain GrEETEC Laboratory Federal University of Rio de Janeiro Rio de Janeiro Brazil materials Laboratory West Zone State University Center (UEZO) Rio de Janeiro Brazil

Hydroesterification process has been presented biodiesel production from oil the green microalga Nannochloropsis oculata raw materials. Biodiesel studied in this work is the main product got from the hydroesterification of biomass the Nannochloropsis oculata and was obtained from esterification of fatty acid (product of a hydrolysis reaction) with methanol. It was used as catalyst the niobic acid pure and supported on δ-aluminum. The product was evaluated by gas chromatography and other analyses. The optimum conditions found in the conversion (%) for the hydrolysis reactions of the biomass (92.3%). Better results were observed in the algae concentration 20%, lead at 300?C with 20% of catalyst. For esterification of fatty acids of Nannochloropsis oculata (92.24%), were observed the molar ratio methanol: fat acid 3, lead at 200°C with 20% of catalyst supported.

关键词： Biodiesel microalgae Hydrolysis Esterification Nannochloropsis oculata

两种不同方法制备的IN939高温合金在长时间时效过程中的组织稳定性的比较(英文)

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Transactions of Nonferrous metals Society of China 2014年第6期24卷 1717-1729页

作者： m.r.JAHANGIrI H.ArABI S.m.A.BOUTOrABI metallurgy Department Niroo Research Institute School of metallurgy and materials Engineering Iran University of Science and Technology

采用光学显微镜、扫描电子显微镜及能谱分析对两种不同方法制备的IN939高温合金在高温、长时间时效过程中的组织稳定性进行研究。结果表明,γ′粒子的粗化行为主要受到初始热处理条件的影响,而之前的制备方法（铸造或热变形）的影响不明... 详细信息

采用光学显微镜、扫描电子显微镜及能谱分析对两种不同方法制备的IN939高温合金在高温、长时间时效过程中的组织稳定性进行研究。结果表明,γ′粒子的粗化行为主要受到初始热处理条件的影响,而之前的制备方法（铸造或热变形）的影响不明显,若有,也只是对γ′粒子的粗化动力学有影响。在790-827℃的温度范围内,铸态或锻态IN939合金样品都有比较好的组织稳定性。在827-910℃的温度范围内,采用初始热处理条件HT1的样品不管是在铸态还是在锻态都有比较好的组织稳定性。

关键词：镍基高温合金 IN939高温合金长时间粗化制备方法热处理 γ'粒子碳化物

Air pollution and meteorological conditions significantly contribute to the worsening of allergic conjunctivitis:a regional 20-city,5-year study in Northeast China

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Light(Science & Applications) 2021年第11期10卷 2128-2142页

作者： Cheng-Wei Lu Jing Fu Xiu-Fen Liu Wei-Wei Chen Ji-Long Hao Xiao-Lan Li om Prakash Pant The Department of Ophthalmology The First Hospital of Jilin UniversityChangchun130021China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun130102China Institute of Atmospheric Environment China Meteorological AdministrationShenyang110166China Dhangadhi Netralaya Eye Hospital Dhangadhi3KailaliNepal

This study is the first to explore the potential associations among allergic conjunctivitis(AC),air pollution,and meteorological conditions in Northeast *** of meteorology,ambient atmospheric pollutants,and the incidence of allergic conjunctivitis(IAC)in prefecture-level cities between the years 2014 and 2018 are *** results show an increasing trend in the AC of average growth rate per annum 7.6%,with the highest incidence in the provincial *** IAC is positively correlated with atmospheric pollutants(i.e.,Pm_(2.5),Pm_(10),CO,SO_(2),NO_(2),and O_(3))and meteorological factors(i.e.,air temperature and wind speed),but negatively correlated with relative *** results suggest that the IAC is directly proportional to pollution level and climatic conditions,and also the precedence of air *** have further obtained the threshold values of atmospheric pollutants concentration and meteorological factors,a turning point above which more AC may be *** with the air quality standard advised by China and the World Health Organization(WHO),both thresholds of Pm_(10)(70μg m^(-3))and Pm_(2.5)(45μg m^(-3))are higher than current standards and pose a less environmental risk for the ***_(2) threshold(23μg m^(-3))is comparable to the WHO standard and significantly lower than that of China’s,indicating greater environmental risks in *** thresholds of NO_(2)(27μg m^(-3))and O_(3)(88μg m^(-3))are below current standards,indicating that they are major environmental risk factors for the *** findings highlight the importance of atmospheric environmental protection and reference for health-based amendment.

关键词： allergic meteorological pollution

Time and reference frequency transfer over 850 nm VCSEL for digital telecommunication network synchronization

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Optoelectronics Letters 2019年第3期15卷 209-212页

作者： G.m.Isoe S.Wassin A.W.r.Leitch T.B.Gibbon Centre for Broadband Communication Nelson Mandela University

Accurate time transfer and synchronization between different network nodes is a key functional requirement in digital communication. Developments in optical fiber-based frequency dissemination techniques have improved optical frequency stability over time to much lower levels. In this work, we experimentally present the reference frequency transfer employing 850 nm vertical cavity surface emitting laser(VCSEL) over 100.3 m om3 multimode fiber for synchronization of clocks on networked devices such as servers and racks/pod at different data center network nodes. A low-cost power-efficient multimode VCSEL with central wavelength at 844.26 nm is directly modulated with a 2 GHz reference frequency(rF) clock signal, and transferred over 100.3 m of om3 multimode fiber. The single side band(SSB) phase noise of-104.62 dBc/Hz and-100.70 dBc/Hz is experimentally measured at back-to-back(B2 B) and 100.3 m om3 multimode fiber transmission respectively at a 1 kHz frequency offset. The jitter stability of 0.14 ps and 0.15 ps is experimentally achieved at B2 B and 100.3 m fiber transmission, respectively. This work provides an alternative viable approach for the development of time keeping devices in high-speed short-reach optical communication systems.

关键词： VCSEL

Exploratory systematic review and meta-analysis on period poverty

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World Journal of meta-Analysis 2023年第5期11卷 196-217页

作者： Gayathri Delanerolle Xiao-Jie Yang Heitor Cavalini om P Kurmi Camilla mørk røstvik Ashish Shetty LuckySaraswat Julie Taylor Sana Sajid Shanaya rathod Jian-Qing Shi Peter Phiri Department of research&Innovation Southern Health NHS Foundation TrustSouthampton SO303JBUnited Kingdom Nuffield Department of medicine University of OxfordOxford OX37JXUnited Kingdom School of Statistics and mathematics Yunnan University of Finance and EconomicsKunming 650221Yunnan ProvinceChina University College London London WC1E 6BTUnited Kingdom Centre for Intelligent Healthcare Institute of Health and WellbeingCoventry UniversityCoventry CV15LBUnited Kingdom Centre for Contemporary Art University of St AndrewsScotland KY169AJUnited Kingdom Pain management Centre University College London Hospitals NHS Foundation TrustLondon W1T 4AJUnited Kingdom Aberdeen Centre for Women’s Health University of AberdeenAberdeen AB243FXUnited Kingdom School of Nursing University of BirminghamBirmingham B152TTUnited Kingdom Statistics and Data Science Southern University of Science and TechnologyShenzhen 518055Guangdong ProvinceChina School of Psychology Faculty of Environmental and Life SciencesUniversity of SouthamptonSouthampton SO171BJUnited Kingdom

BACKGrOUNDPeriod poverty is a global health and social issue that needs to be *** has been reported that many females com.romise their education,employment,and social commitments during their menstruation days due to a number of reasons,including lack of access to toilets or menstrual *** To provide a com.rehensive understanding on period poverty,including outcomes associated with *** All observational and randomised clinical trials reporting menstruation challenges,menstrual poverty and menstrual products were *** search strategy included multiple electronic databases of Pubmed,Web of Science,ScienceDirect,ProQuest and *** published in a peer review journal in English between the 30th of April 1980 and the 30th of April 2022 were *** Newcastle-Ottawa Scale was used to assess the risk of bias of the systematic included *** odds ratios(Ors)together with 95%confidence intervals(CIs)are reported overall and for *** A total of 80 studies were systematically selected,where 38 were included in the *** the 38 studies,28 focused on children and young girls(i.e.,10-24 years old)and 10 included participants with a wider age range of 15-49 *** prevalence of using disposable sanitary pads was 45%(95%CI:0.35-0.58).The prevalence of menstrual education pre-menarche was 68%(95%CI:0.56-0.82).The prevalence of good menstrual hygiene management(mHm)was 39%(95%CI:0.25-0.61).Women in rural areas(Or=0.30,95%CI:0.13-0.69)were 0.70 times less likely to have good mHm practices than those living in urban *** There was a lack of evidence,especially from low-and middle-income *** research to better understand the scope and prevalence of period poverty should be *** will enable the development of improved policies to increase access to menstrual products and medical support where necessary.

关键词： Period poverty menstruation mental health menstrual education menstrual hygiene

在单频激光辐射作用下,玻璃光学击穿阀的时间关系研究

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云光技术 1998年第2期30卷 29-35页

作者： E.,om 艾必惠

在辐射聚焦成０．５－２０μｍ不同直径光斑的情况下，对ＫＳ玻璃的光学击穿阈与激光辐射脉冲持续时间的关系进行了测定。

关键词：激光辐射 KS玻璃光学击穿阈玻璃光学

腐蹄病节瘤拟杆菌纤毛蛋白与绵羊白细胞介素-2融合基因表达载体的构建及表达

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中国兽医学报 2002年第2期22卷 131-133页

作者：王克坚 om Dhungyel 余兴龙冯书章赵宝华 Jr Egerton 朱平殷震中国农业科学院吉林特产研究所吉林吉林市132109 澳大利亚悉尼大学解放军军需大学军事兽医研究所吉林长春130062

根据腐蹄病节瘤拟杆菌纤毛蛋白基因 (Pili基因 )序列 ,在 Pili基因 6 19bp Ehe 酶切位点上插入绵羊白细胞介素 - 2基因 (Ovi IL- 2基因 ) ,构建了 Pili基因与 Ovi IL- 2基因的融合基因表达载体。先用 Eco r 、Bam H 双酶切p Bluescript-... 详细信息

根据腐蹄病节瘤拟杆菌纤毛蛋白基因 (Pili基因 )序列 ,在 Pili基因 6 19bp Ehe 酶切位点上插入绵羊白细胞介素 - 2基因 (Ovi IL- 2基因 ) ,构建了 Pili基因与 Ovi IL- 2基因的融合基因表达载体。先用 Eco r 、Bam H 双酶切p Bluescript- Ovi IL - 2重组质粒 ,获得两端具有 Eco r 、Bam H 位点的 Ovi IL - 2基因片段 ,用 Klenow补平后 ,与经Ehe 酶切后的重组质粒 PmE2 90 - Pili进行平端连接 ;转化 Jm10 5感受态细胞 ,筛选阳性克隆 ,分别用 Bam H 、Eco r 、Xba 、Bgl 、Pvu 等进行酶切鉴定。然后将阳性重组质粒转染 BL - 2 1表达宿主感受态细胞 ,用 0 .1m ol/ L mg Cl2沉淀法和超声波裂解法提取 BL- 2 1表达 Pili基因与 Ovi IL- 2基因融合基因表达蛋白。对流免疫电泳对重组融合蛋白的特异性分析证明 ,融合蛋白主要在宿主菌体中表达 ;SDS- PAGE电泳结果表明 ,重组融合蛋白分子大小约为 330 0 0 ,表达产物的量约占菌体的 5 .49%。

关键词：腐蹄病节瘤拟杆菌纤毛蛋白基因绵羊白细胞介素2基因基因工程疫苗免疫

Direct Current Interruption with rLC Circuit-convoluted Arc Interaction

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高电压技术 2013年第9期39卷 2166-2172页

作者： Leonid m. Shpanin Noel Y. A. Shammas Sarath B. Tennakoon Gordon r. Jones Jim E. Humphries Joseph W. Spencer Staffordshire University Stafford ST 180AD United Kingdom University of Liverpool Liverpool L69 3G J United Kingdom

Investigations are reported into the use of an electromagnetically convoluted arc,external to a magnetic field(B-field)producing coil,in combination with a parallel r,L,C resonant circuit for interrupting quasi-steady *** order to elucidate the complex interactions between the arc,B-field and r,L,C circuit,the B-field producing coil is energised independently from the current to be interrupted and the r,L,C *** results are presented for the time variation of the currents flowing through the arc gap,the B-field coil and the parallel r,L,C circuit,along with the voltage across the arc *** insight is gained into the role of various effects,which are produced by the complex interactions and which might be used to advantage for direct current interruption.

关键词： rLC电路稳态电流中断相互作用调查报告谐振电路磁场线圈

巴西马拉若岛上应用电磁法勘探寻找地下水野外结果

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国外地质勘探技术 1990年第7期 30-31页

作者： om Prakesh Verma 张明华

嵌于含盐水泥质之中的地下淡水河及其它含淡水的砂砾为一种导电半空间中的高阻体的地电条件。在测区内覆盖着从中新世到全新世的帕拉组碎屑沉积岩。使用880Hz和2640Hz两个频率,横跨瓜热拉米林地下河进行了Em试验剖面测量。剖面使用了垂... 详细信息

嵌于含盐水泥质之中的地下淡水河及其它含淡水的砂砾为一种导电半空间中的高阻体的地电条件。在测区内覆盖着从中新世到全新世的帕拉组碎屑沉积岩。使用880Hz和2640Hz两个频率,横跨瓜热拉米林地下河进行了Em试验剖面测量。剖面使用了垂直共轴、垂直共面和水平共面线圈耦合方式的同线法测量,线圈距为50m。旁线法的Em地面剖面测量,由于参考电缆的障碍而无法进行。我们在保持发射机位于第2测点、接收机位于第3测点的状态下进行的仪器校准。这两个点大致位于河道中心。异常幅值最高。

关键词：电磁法勘探地下水