二道沟水电站移民安置调研分析

二道沟水电站是牡丹江流域4个梯级开发电站之一,总库容1.28亿m3,库区淹没面积较大.文章对库区的自然资源、交通等条件,通过调研初步提出了电站移民安置规划.     

Analysis of four tobacco-specific nitrosamines in mainstream cigarette smoke of Virginia cigarettes by LC-MS/MS

An improved method was developed for the determination of the four major tobacco-specific nitrosamines（TSNAs） in mainstream cigarette smoke. The new method offers decreased sample preparation and analysis time as compared to traditional methods. This method uses isotope dilution liquid chromatography coupled with a tandem mass spectrometer with electrospray ionization and is significantly more sensitive than traditional methods. It also shows no evidence of artifactual formation of TSNAs. Sample concentrations were determined for four TSNAs in mainstream smoke using two isotopically labeled TSNAs analogues as internal standards. Mainstream smoke was collected on an industry standard 44-ram Cambridge filter pad, extracted with 0.1 mol/L ammonium acetate, purified by solid-phase extraction, and analyzed without further sample cleanup. The analytical column is a 3.9 mm×150 mm Waters Symmertry Shield RP18 column and volume fraction of the mobile phase is 50% methanol, 50% water containing 0.1% acetic acid. The results show that the linear range is 0.5-100.0 mg/L except for N-nitrosoanabasine （NAB） from 0.25 to 50.0 mg/L. The limits of detection are 0.1 mg/L for N-nitrosonornicotine （NNN）, 0.08 mg/L for 4-（methylnitrosamino）-1- （3-py-ridyl）-1-butanone （NNK）, 0.05 mg/L for N-nitrosoanatabine （NAT） and 0.06 mg/L for NAB. The recoveries of the four TSNAs are from 90.2% to 105.7%.     

桥梁施工中双掺混凝土的应用

普通混凝土掺入"双掺"不仅能起到改善混凝土性能,且提高强度和抗冻等级,并能改善环境,具有一定的经济效益和推广应用价值.     

龙虎山水电站水库淹没区耕地垫高的策略分析

龙虎山水电站位于黑龙江省林口县境内的牡丹江干流上,距上游莲花水电站29 km,是牡丹江下游的梯级水电站之一.库区内主要是居民区,农用耕地和林地.该地区也是林口县比较富庶的地区之一,是全国烤烟基地镇.移民安置规划设计工作中大部分耕地淹深3 m以内,为了保护及合理开发利用耕地,减少失地农业人口数量,增加移民安置环境容量,减少移民生产安置难度,在充分分析水库淹没区的自然状况和社会经济现状的基础上提出了耕地垫高方案,即把水库淹没区淹深较浅的耕地或者浸没的耕地垫高,保证这部分耕地不再受水库淹没影响,原有的耕种功能不变.     

二道沟水电站移民安置调硏分析

二道沟水电站是牡丹江流域4个梯级开发电站之一,总库容1.28亿m^3,库区淹没面积较大。文章对库区的自然资源、交通等条件,通过调研初步提出了电站移民安置规划。     

二道沟水电站水土保持方案

根据二道沟水电站所在影响区域的地理、地形、地质、植被及土壤情况,对其水土保持方案进行分区.     

Determination of constituents of essential oil from Angelica sinensis by gas chromatographymass spectrometry

1INTRODUCTION TraditionalChinesemedicines(TCMs)are veryimportantduetotheirextensiveuseinpre ventingandcuringmanydiseasesforhumans.Al thoughonlysomecompoundsmightberesponsible forpharmaceuticaleffects,traditionalChinese medicinesusuallycontaintoomanycomponentsandformaverycomplexsystem,whichmakesthe screeningandanalysisofbioactivecomponentsex tremelydifficult[1]comparedwiththoseofwesternmedicines.Whensuchcomplexsamplesareana lyzed,itiscommonthatdifferentcontentsof multi componentsandgreatd…     

二道沟水电站的水文分析

二道沟水电站位于牡丹江下游林口县境内,是已建莲花水电站下游的首座梯级电站.对其控制流域的水文特征进行了系统分析.     

Determination of constituents of essential oil from Angelica sinensis by gas chromatography-mass spectrometry

Gas chromatography-mass spectrometry （GC-MS） coupled with chemometric resolution upon twodimensional data was employed to analyze the constituents of essential oils of Angelica sinensis. Constituents in essential oils of Angelica sinensis root were identified by GC-MS with the help of subwindow factor analysis （SFA） method resolving two-dimensional original data into mass spectra and chromatograms. 76 of 97 separated constituents in essential oil of Angelica sinensis root were identified and quantified, and they account for about 91.36% of the total content. The results show that ligustilide, butylene phthalide, 2-methoxy-4-vinylphenol, carvacrol, alloocimene, 2,6,6-trimethylbicyclo-[3,1,1] hept-2-ene are the main constituents in essential oil of Angelica sinensis root.     

应用纤维素测定仪测定烟草中的纤维素

以石英砂为助滤荆,采用Fibertec2010型纤维素测定仪测定了31个烟草样品中半纤维素、纤维素、酸性洗涤木质素(ADL)和粗纤维素含量.结果表明:①该测定仪6根浸提柱同时分析烟叶中半纤维素、纤维素、ADL和粗纤维素的相对标准偏差(RSD)分别为2.82%、1.71%、4.79%、1.77%,1根浸提柱4次重复分析的RSD分别为1.61%、1.06%、3.72%、1.80%;②同一品种3部位烟叶的半纤维素、纤维素、ADL和粗纤维素的含量差别不大;③白肋烟中的纤维素和粗纤维素的含量明显高于烤烟;④再造烟叶中的纤维素和粗纤维素含量远高于烤烟各组分的含量;⑤与低档卷烟相比,高档卷烟的半纤维素含量高,纤维素、ADL和粗纤维素含量低.