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81.
以薏米和枸杞为主要原料制成一种保健饮品。通过正交试验,确定最佳生产配比为:蔗糖5%,柠檬酸0.2%,薏米、枸杞的比例为3∶1。对饮料的可溶性固形物、酸度、还原糖、金属元素、氨基酸含量等指标进行测定。结果为:可溶性固形物5.76%;pH值5.42;还原糖含量17.9mg·L-1。Zn、Mg、Na、Fe、Mn、Ca、K等7种金属元素的含量分别为0.0045,4.7855,35.1020,0.0169,0.0060,4.7429,22.3690g·L-1。Cd、Pb、Cr、Cu、Co等均未测出,且含有16种氨基酸,总量为22.79μg·L-1。  相似文献   
82.
The large volume of cellulose products, primarily newsprint and yard waste, that are disposed of in landfills and the resistance of these products to decomposition led to an evaluation of the disposal of ground newsprint on agricultural land. A field study was conducted with cotton to evaluate the effects of trenching and mixing the excavated soil with ground newsprint and/or poultry litter. Decomposition rate of newsprint and potential for environmental contamination were investigated in a Cahaba-Wickham-Bassfield sandy loam (Typic Hapludult) soil. The experimental variables included different ratios of soil, ground newsprint, and/or poultry litter applied on the soil surface and in trenches 0.61 m or 1.22 m deep. When ground newsprint and excavated soil were mixed without adjusting the C:N ratio of the backfill, the newsprint was still present seven months after application. However, adjusting the C.N ratio of the excavated soil and ground newsprint with poultry litter provided the nitrogen necessary to completely decompose the ground newsprint within seven months. Soil surface application of ground newsprint required adjusting the C:N ratio to control the occurrence of plant pathogenic organisms. Extractable soil nutrients were increased when poultry litter was added, including P and K which are of concern with respect to surface and groundwater contamination. Extractable Zn, Cu, and Mn levels were increased by the addition of poultry litter, but their levels were in the ranges that most row crops will tolerate. The metals Cr and Pb, found in some printer's ink, may be of concern if repeated application of newsprint is made to the same site. Soil organic matter content was increased from 11.9 g kg-1 to 23.8 g kg-1 in the 50:40:10 backfill mixture of soil, newsprint, and poultry litter seven months after application.  相似文献   
83.
Snow cover is an important water source for vegetation growth in arid and semi-arid areas,and grassland phenology provides valuable information on the response of terrestrial ecosystems to climate change.The Mongolian Plateau features both abundant snow cover resources and typical grassland ecosystems.In recent years,with the intensification of global climate change,the snow cover on the Mongolian Plateau has changed correspondingly,with resulting effects on vegetation growth.In this study,using MOD10A1 snow cover data and MOD13A1 Normalized Difference Vegetation Index(NDVI)data combined with remote sensing(RS)and geographic information system(GIS)techniques,we analyzed the spatiotemporal changes in snow cover and grassland phenology on the Mongolian Plateau from 2001 to 2018.The correlation analysis and grey relation analysis were used to determine the influence of snow cover parameters(snow cover fraction(SCF),snow cover duration(SCD),snow cover onset date(SCOD),and snow cover end date(SCED))on different types of grassland vegetation.The results showed wide snow cover areas,an early start time,a late end time,and a long duration of snow cover over the northern Mongolian Plateau.Additionally,a late start,an early end,and a short duration were observed for grassland phenology,but the southern area showed the opposite trend.The SCF decreased at an annual rate of 0.33%.The SCD was shortened at an annual rate of 0.57 d.The SCOD and SCED in more than half of the study area advanced at annual rates of 5.33 and 5.74 DOY(day of year),respectively.For grassland phenology,the start of the growing season(SOS)advanced at an annual rate of 0.03 DOY,the end of the growing season(EOS)was delayed at an annual rate of 0.14 DOY,and the length of the growing season(LOS)was prolonged at an annual rate of 0.17 d.The SCF,SCD,and SCED in the snow season were significantly positively correlated with the SOS and negatively correlated with the EOS and LOS.The SCOD was significantly negatively correlated with the SOS and positively correlated with the EOS and LOS.The SCD and SCF can directly affect the SOS of grassland vegetation,while the EOS and LOS were obviously influenced by the SCOD and SCED.This study provides a scientific basis for exploring the response trends of alpine vegetation to global climate change.  相似文献   
84.
中间偃麦草、长穗偃麦草及其杂种F1代同工酶研究   总被引:1,自引:0,他引:1  
通过对过氧化物酶(POD)、酯酶(EST)、超氧化物歧化酶(SOD)和多酚氧化酶(PPO)同工酶谱的分析,探讨中间偃麦草(Elytrigia elongata(Host)Nevski)、长穗偃麦草(E.intermedia(Host)Nevski)及其杂种F1代的酶谱特征和亲缘关系。结果表明:亲本同工酶酶带数目、迁移率、着色程度等差异不大,二者亲缘关系较近。与亲本相比,杂种F1代存在POD、SOD、PPO酶带丢失现象,但正、反交植株中均产生了一些亲本没有的新生带。杂种F1代EST酶谱与亲本基本相同,仅着色程度略有差异。杂种F1代植株的POD、PPO酶谱特征有偏向中间偃麦草的倾向,而SOD酶谱特征倾向于长穗偃麦草。杂种F1代同工酶具有多态性,可作为遗传标记用于杂种鉴定和后代株系目标性状的选择。  相似文献   
85.
中国苜蓿审定登记品种叶形态特征及变异分析   总被引:2,自引:0,他引:2  
徐春波  于林清  王勇  萨仁 《草地学报》2007,15(3):243-247,268
利用CI-202型叶面积仪研究29个我国审定登记苜蓿品种(Medicago sativa L.)的叶长、叶宽、叶面积、叶周长、叶长/叶宽和叶形指数。结果表明:地方苜蓿品种和育成品种在叶形态方面存在着较大的差异,前者的叶片较后者小;二者叶片形状相似;在6个指标中,叶长宽比变异最大,叶周长变异最小;地方品种的叶面积、叶长、叶周长和叶长宽比的变异系数均高于育成品种,其他2项指标则低于后者;在育成品种中,中兰1号的变异最大,甘农3号苜蓿最小;在地方品种中,蔚县苜蓿的变异最大,河西苜蓿最小;该结果将为今后培育苜蓿新品种提供理论基础。  相似文献   
86.
为探究羊经布鲁菌病疫苗(S2株)免疫后的血清抗体长期动态消长规律,本试验于2012年9月-2015年9月选取阿拉善盟阿拉善左旗96只山羊、100只绵羊作为试验动物,经布鲁菌疫苗(S2株)100亿CFU、200亿CFU不同免疫剂量灌服,分别于免疫前和免疫后不同时间段采血分离血清,应用虎红平板凝集试验和试管凝集试验进行抗体监测。结果表明,绵羊组在一免后20d时,血清抗体阳性率达到最高峰,之后呈下降趋势,150d抗体阳性率降至0%,免疫后180d^360d,绵羊组抗体阳性率一直处于较低水平(0%~4%),二免和三免后不同时间段免疫抗体消长规律与首次免疫基本一致;山羊组抗体阳性率在免疫后20 d时,血清抗体阳性率达到最高峰,之后呈下降趋势,免疫后90 d^360 d,免疫抗体时高时低,起伏较大,无明显规律,二免和三免后不同时间段免疫抗体消长规律与首次免疫基本一致,结果同时表明,100亿CFU和200亿CFU两个免疫剂量组的抗体阳性率无明显差异。  相似文献   
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88.
陕北毛乌素沙地仁用杏丰产栽培技术体系   总被引:6,自引:2,他引:4  
针对陕北毛乌素沙地地势较为平埋,光热资源丰富,水资源相对充足,但干旱少雨,降水集中,蒸发量大,风沙危害频繁,土质疏松、漏肥、漏水现象严重等特殊的自然条件,提出了适宜该地区采用的仁用杏丰产栽培技术体系。  相似文献   
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