简介:Thedistributionofrareearthelement(REE)formsinsoilsisgiveninthepresentpaperonthebasisofsequentialfractionationanddeterminationof34representativesurfacesoilscollectedfromallpartsofChina.ResultsobtainedshowthattheextractionrateofwatersolubleandexchangeableREEhadtheodd-evenphenomenonandthatoforganicallyboundREEfromLatoLutendedtoreducegraduallywiththeincreaseofatomicnumber.ThestabilityofScandtheactivityandenrichmentofTminsoilsareproposed.Furthermore,thepapermakesapreliminarydiscussiononthedifferencesintheconcentrationdistributionofvariousformsofindividualREEinsomesoils.
简介:Chinesefir(Cunninghamialanceolata)andpoplar(Populusspp.)woodmealwerephenolatedinthepresenceofsulfuricacidusedasacatalyst.Theeffectsofreactiontimeandreactiontemperatureonthewoodliquefactionwereinvestigated.Theresultsshowedthatthereactiontemperaturehadthegreaterinfluenceontheresiduecontentthanreactiontime.Additionally,theliquefactioncurvefortheChinesefirandPoplarweresimilaringeneral.
简介:Adsorptionanddesorptionofexogenousrareearthelements(REE)insoilswerestudied.ResultsshowedthatsoilshadstrongadsorbabilityforREEandtherateofadsorptionofREEwasover95%oftheaddedREEinthesetests.ThecharacteristicsofadsorptionisothermscorrespondedwellwiththebothFreundlichandTemkinequations,butdeviatedfromtheLangmuirequation.TheadsorptionofREEtendedtoincreasewiththerisingofsoilpH.AsequentialextractionmethodusedforstudingthedesorptionanddistributionofREEsorbedinsoilsarealsodiscussed.
简介:10月25日,沈阳市商业局和财政局联手出击,30部检测“注水猪肉”的先进仪器,进驻沈阳市(区、县)8个生猪定点屠宰监督检查部门和全市21家生猪定点屠宰场,严把猪肉市场流通关,让市民吃上放心肉。
简介:Endophyticfungiarewidelyfoundinalmostallkindsofplants.Manyendophyticfungicanproducesomephysiologicalactivecompounds,whicharesametooranalogtothoseisolatedfromtheirhosts.Producingphysiologicalactivecompoundsthroughmicrobialfermentationcangiveanewwaytoresolveresourcelimitationandtofindoutalternativesource.Throughthemethodsoforganicsolventextraction,thinlayerchromatography(TLC)andcolumnchromatography,compoundIwasisolated,purifiedfromtheliquidfermentationmetabolitesofthetaxoids-producedendophyticfungi(Alternaria.alternatavar.taxi1011Y.XiangetLUAn-guo)thatwasscreenedfromthebarkofTaxus.cuspidataSieb.etZucc..CompoundIwasidentifiedasonekindoftaxoidstypeIII,basedontheanalyzingresultsbyusingthemethodsofultravioletspectroscopy(UV),infraredspectroscopy(IR),massspectrometry(MS)andnuclearmagneticresonancespectroscopy(NMR).Thisstudyprovidesacompletedmethodforseparationandpurificationoftheendophyticfungiaswellasstructureidentificationofitsfermentationmetabolite
简介:I-69杨插穗分别培养在含有不同浓度Ce(NO3)3的营养液中,经快速冷冻、冷冻干燥、无水塑料包埋及干刀薄切片法,用X-射线能谱微区分析测定Ce及其它无机离子在茎尖分生组织和叶的不同组织中细胞壁、细胞质、细胞核及叶绿体中的含量及分布。在10ppmCe(NO3)3处理下,茎尖中Ce的含量比对照组和100ppmCe(NO3)3处理组高出近1倍,叶的亚细胞中的K、P、S、Fe的含量也呈增加的趋势。特别是Mg的含量增加显著,在保卫细胞的细胞质中Mg的含量比对照组高出3.5倍,而在表皮细胞的细胞核和液泡中的含量则比对照组高出近13倍。但在100ppmCe(NO3)3处理下,无机离子在叶中亚细胞微区间的含量则显著下降
简介:一,用途及特点为了解决在象片比例尺不等的象对上,进行立体观察,剌点和转绘,我们试制了立体变倍判读仪。具有简单,灵活、轻便、效率高、用途广和适应内外业环境能力的特点。一九八八年十二月,我们承担编制敦化市林业局秋梨沟林场的象片平面图,由于外业调绘片与象片平面图比例尺不等(1:35000和1:25000)造成转绘上的困难,于是通过实践试制了立体变倍判读仪,效果很好,具有简单,灵活、轻便、效率高、用途广等特点。二、试制变倍升降台它是立体镜的补助设备,试制的目的就是使它配合立体镜解决判读准确,提高转绘效率问查。即既能形成立体模型,还要保证模型的比例尺。