检索结果-南通市图书馆

Science China Chemistry 1993年第2期36卷 151-161页

作者：肖丰收徐如人 Ichikawa Masaru Fukuoka Atsushi Shriver D.F henderson w 郭燮贤辛勤 Department of Chemistry Jilin University Changchun 130023 PRC Catalysis Research Center Hokkaido University Sapporo 060 Japan Department of Chemistry Northwestern University Evanston IL 60208-3113 USA National Lab. for Catalysis Dalian Institute of Chemical Physics Academia Sinica Dalian 116023 PRC

The bimetallic Ru-M (M=Co,Fe,Ni,Mo, Rh,Cr, Mn) catalysts were prepared from SiO_2-supported bimetallic carbonyl clusters, and it was found that the Ru-Co, Ru-Fe and Ru-Mo bimetallic carbonyl cluster-derived catalysts showed higher activity and selectivity for oxygenates such as C_1-C_5 alcohols in CO hydrogenation,in contrast to catalysts prepared from SiO_2-supported homometallic Ru and Co carbonyl clusters. In situ FT-IR studies revealed that the bands at 1584 and 1555 cm^(-1) species were intermediates to produce methanol and higher oxygenates,and at higher temperatures the 1584 cm^(-1) species could react with alkyl to form 1555 cm^(-1) species. By the surface chemical reaction and the IR study of isotopic molecules,it was suggested that 1584 and 1555 cm^(-1) were assigned to surface formyl and acetyl species.

关键词： bimetallic carbonyl cluster Ru eluster bimetallie eatalyst CO hydrogenation oxygenates IR spectra surface formyl and aeetyl.

THE PATENTABILITY OF SOFTwARE AND MATHEMATICAL ALGORITHMS FOR COMPUTATIONAL ELECTROMAGNETICS

在线全文

学校读者我要写书评

暂无评论

THE PATENTABILITY OF SOFTWARE AND MATHEMATICAL ALGORITHMS FO...

Developmental assets and age of first sexual intercourse among adolescent African American males in Mobile, Alabama

1999 International Conference on Computational Electromagnetics and Its Applications(ICCEA’99)

作者： Lee w.henderson Knobbe MartensOlson ＆ Bear LLP 620 Newport Center Drive Newport BeachCalifornia U.S.A.92660 Ph.D.

＜正＞Introduction In the U.S.,software has been patentable subject matter for many years. Nevertheless,until very recently,it was not uncommon to hear engineers,and even some patent attorneys,assert that software was not *** patentability of mathematical algorithms in the *** not so clear cut,but recent changes in *** law have expanded the scope of patentability for mathematical *** types of mathematical algorithms that were

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Health 2013年第6期5卷 26-32页

作者： Shannon Talbott Jessica w. henderson Linda Stonecipher John Bolland Brad Lian College of Health University of Utah Salt Lake City USA Division of Allied Health Indiana University Kokomo USA Graduate Studies Western Oregon University Monmouth USA School of Public Health University of Alabama Birmingham USA

Background and Aims: Younger age at first sexual intercourse is associated with a variety of adverse health outcomes. we aimed to gain a clearer understanding of a wide range of individual, family and social factors that may influence sexual behavior of children and adolescents. Specifically, we examined the relationships of developmental assets with age of first sexual intercourse among a large sample (n = 1061) of adolescent African American males living in low-income neighborhoods in Mobile, Alabama. Methods: Using the Developmental Asset Model as a theoretical guide, we selected variables from adolescent survey data and conducted logistic regression analysis to determine predictors of early age of first sexual intercourse. Results: Nearly one half (49%) of the male survey participants reported that they first had sexual intercourse at the age of 12 or younger. The total number of assets was the strongest predictor of later age (13 years old or later) of first sexual intercourse (OR 1.49, 95% CI = 1.09, 2.04), followed by decision-making skills (OR 1.40, 95% CI = 1.04, 1.86), and positive view of the future (OR 1.36, 95% CI = 1.02, 1.74). Conclusion: There are several developmental assets related to the age of first sexual intercourse. This study found support for the Developmental Asset Model as a framework for promoting sexual and overall adolescent health. Recommendations for asset-building among this population are discussed.

关键词： Developmental Assets Adolescence Sexual Behavior African American Males

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

先进的砷化镓制造设备

上海航天 1989年第5期6卷 61-62页

作者： Brecuk w.henderson 自力

哈里斯微波半导体公司研制了一种先进的GaAs(砷化镓)制造设备,力图成为军用单片微波集成电路(MMIC)的主要生产厂家.哈里斯公司掌握GaAs MMIC从晶体生长(几乎不用铸造工艺)到封装整个电路的每一道生产工序.该公司已对生产厂和设备投资了3... 详细信息

哈里斯微波半导体公司研制了一种先进的GaAs(砷化镓)制造设备,力图成为军用单片微波集成电路(MMIC)的主要生产厂家.哈里斯公司掌握GaAs MMIC从晶体生长(几乎不用铸造工艺)到封装整个电路的每一道生产工序.该公司已对生产厂和设备投资了3000万美元,雇用人员仅70人,年产近 5万个MMIC和多达40万个微波元件(如场效应晶体管).年销售额达1000万美元.哈里斯同通用电气和休斯公司一起参与了DARPA(国防预研项目局)的微波/毫米波MMIC硬件研制计划第一阶段的机载和陆基雷达系统研究工作.

关键词：砷化镓制造设备单片集成电路

担载的Ru-M(M=Co,Fe,Mo,Ni,Rh,Mn,Cr)原子簇催化剂在CO+H_2反应中的催化行为研究

在线全文

学校读者我要写书评

暂无评论

中国科学（B辑） 1992年第6期B卷 568-574页

作者：肖丰收徐如人市川胜福冈淳 D.F.Shriver w.henderson 郭燮贤辛勤吉林大学化学系长春130023 日本北海道大学触媒化学研究中心美国西北大学化学系大连化学物理研究所国家催化基础研究实验室大连116023

本文描述了一系列SiO_2担载的Ru和Ru-M(M=Co,Fe,Mo,Ni,Rh,Mn,Cr)双金属原子簇催化剂的制备,并发现在CO+H_2反应中,若和担载的Ru原子簇催化剂相比,Ru-Co/SiO_2,Ru-Fe/SiO_2和Ru-Mo/SiO_2催化剂显示了较高的含氧化合物的生成速率和选择性... 详细信息

本文描述了一系列SiO_2担载的Ru和Ru-M(M=Co,Fe,Mo,Ni,Rh,Mn,Cr)双金属原子簇催化剂的制备,并发现在CO+H_2反应中,若和担载的Ru原子簇催化剂相比,Ru-Co/SiO_2,Ru-Fe/SiO_2和Ru-Mo/SiO_2催化剂显示了较高的含氧化合物的生成速率和选择性。原位的红外光谱揭示了1584和1555cm^(-1)物种是生成甲醇和高级含氧化合物(C_2以上)的中间体,并在较高温度下1584cm^(-1)物种可以与表面烷基反应形成1555cm^(-1)新物种。通过表面化学反应和同位素标记的红外研究,提出了1584cm^(-1)和1555cm^(-1)分别归属于表面甲酰基和酰基。

关键词：双金属原子簇加氢一氧化碳催化

水分和氮素的互作对玉米衰老的影响 Ⅰ.绿叶持续期、氮素分配和产量

在线全文

学校读者我要写书评

暂无评论

园艺与种苗 1989年第5期 15-20页

作者： D.w.woIfe D.w.henderson 廖嘉玲

由於衰老降低了有效光合面积而影响到作物产量,故在经济上很重要。已证实了在一些植物物种上亏水能产生脱叶或衰老的反应。有关玉米的一些研究报告指出,在田间亏水条件下叶面积指数(LAI)下降得很快,籽粒灌浆期间

关键词：氮素分配互作玉米产量籽粒灌浆叶面积指数叶面积系数叶片发育叶水势持续期

水分和氮素的互作对玉米衰老的影响 Ⅱ.单个叶片光合作用衰减及其寿命

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

园艺与种苗 1989年第5期 21-25页

作者： D.w.wolfe D.w.henderson 王长宏

衰老是一个重要的植株发育过程,但迄今没有明确的定义,对其起因也没有查明。最近一些研究认为,衰老过程主要是受遗传控制,但关于生长调节剂和环境因子(例如光照、温度、株间和株内的水分及养分竞争)修饰遗传的程度尚不清楚。本研究中的... 详细信息

衰老是一个重要的植株发育过程,但迄今没有明确的定义,对其起因也没有查明。最近一些研究认为,衰老过程主要是受遗传控制,但关于生长调节剂和环境因子(例如光照、温度、株间和株内的水分及养分竞争)修饰遗传的程度尚不清楚。本研究中的“衰老”系指叶

关键词：叶片光合作用互作氮含量氮素叶绿素含量玉米

眼睑痉挛和偏侧面部痉挛的肉毒杆菌毒素剂量个体化滴定和顽固性病例的治疗

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

世界核心医学期刊文摘(眼科学分册) 2006年第12期 55-56页

作者： Ortisi E. henderson H.w.A. Bunce C. 杨秀梅 Moorfields Eye Hospital LondonUnited Kingdom

Purpose: To evaluate a protocol for the treatment of facial dystonias. Method: A retrospective noncomparative interventional case series of all patients who attended a specialised tertiary referral clinic between January 2000 and January 2003. At the start of treatment, patients were seen and treated at weekly intervals until their symptoms were controlled or they developed complications. The sum of the weekly doses was taken as the individual patient dose and then given at 3-4 monthly intervals as required for the individual patient. Refractory cases of spasm underwent orbicularis muscle reduction. Pretarsal spasm was treated with pretarsal botulinum toxin. If the spasm was relieved but the patient could not open their eyelids, a trial of ptosis props was undertaken and the toxin injections continued, before considering a brow suspension. If patients could not see because of a spastic Bell's phenomenon, they were given centrally acting systemic medication. Results: Of 182 new patients, 63 (35%) required two or more sets of injections to titrate their optimum dose of toxin. Symptoms improved in 169 patients (93%). Of a total 332 new patients and follow-up patients, 47 (14%) underwent surgery during their management, 36 protractor myectomy, and 13 brow suspension. Protractor myectomy improved symptoms in 23 (64%). Brow suspension improved symptoms in 12 patients (92%). Conclusions: The dose of botulinum toxin can be titrated to the individual patient, and the refractory cases managed satisfactorily if a logical protocol is followed.

关键词：肉毒杆菌毒素个体化眼轮匝肌缩短术额肌悬吊术剂量用药量顽固性滴定病例

接受非心脏手术的老年患者术前血细胞比容水平与术后结果

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

世界核心医学期刊文摘（心脏病学分册） 2007年第10期3卷 13-页

作者： Schifftner T.L. henderson w.G. 刘少伟

背景:老年患者具有较高的血细胞比容异常和非心脏手术后心血管并发症的风险。虽然术前对患者血细胞比容异常水平的筛查已非常普遍,但是少有证据显示术前贫血或红细胞增多症的不良影响。目的:在接受较大非心脏手术的老年退伍军人中。

关键词：血细胞比容老年退伍军人血液检查心脏手术心脏外科手术术前老年患者

High-resolution precipitation variations in the Northeast Tibetan Plateau over the last 800 years documented by sediment cores of Qinghai Lake

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2003年第14期48卷 1451-1456页

作者： ZHANGJiawu JINMing CHENFahu R.w.Battarbee A.CoG.henderson CenterforAddEnvironmentandPaleoclimateResearch NationalLab.ofWesternChina'sEnvironmentalSystemLanzhouUniversityLanzhou730000China DesertandDesertificationLab. ColdandAridRegionsEnviron-mentalandEngineeringResearchInstituteChineseAcademyofSci-encesLanzhou730000China EnvironmentalChangeResearchCenter DepartmentofGeographyUniversityCollegeLondon26BedfordWayWC1H0APUK

Short cores of about 80-cm retrieved from three main basins of the deepwater areas in Qinghai Lake, the largest inland enclosed lake in China, were studied. Stable isotopes of authigenic carbonates, grain-size, carbonate and organic matter content at 5-year resolution are used to reconstruct the climatic history over the last 800 years in the Northeastern Tibetan Plateau. Chronology was established according to 210Pb dating and 137Cs methods and the core correlation. It is found that cores from different deep basins of the lake can be well correlated. The sedimentary rate is highest in the western basin of the lake and lowest in the east. In the southern basin of the lake where the short core Qing-6 is located, the recent average sedimentation rate is 0.1004 cm/yr. Variations in effective precipitation recorded by the oxygen isotopes and grain size data during the last 800 years are consistent with the glacial accumulation record form the Dunde and Guliya ice cores. A dry climate lasted for 300 years from 1200 AD to 1500 AD, followed by a wet period from 1500 to 1560 AD. The two dry periods, 1560 to 1650 AD and 1780 to 1850 AD, were the results of southwest monsoon weakening. The effective precipitation generally increased since 1650 AD due to the strengthening of the Asian Southwest Monsoon, resulting in a wet period until the 1950s. Except the early stage, the Little Ice Age on the Plateau is characterized by increased effective moisture. Organic mat- ter content, with nearly 200-year cycles, shows similar trend with the atmospheric delta carbon-14 before the 1850s, indicating that the bioproductivity responds to solar activity.

关键词：中国西藏东北部青海湖沉积岩心古气候碳酸盐氧同位素有效降水量