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831.
贺兰山东麓暴雨环流统计预报模型 总被引:3,自引:1,他引:2
利用同期NCAR/NCEP逐日全球再分析资料,以贺兰山东麓40次暴雨天气过程为研究对象,分析得到4种主要环流背景:两脊一槽、两槽一脊、一脊一槽、一槽一脊。其中,两脊一槽环流形势下发生暴雨的可能性最大,两槽一脊、一脊一槽环流形势下发生暴雨的可能性基本相当,一槽一脊较少。并对同一环流背景不同天气过程环流形势进行了合成分析,分析了贺兰山东麓暴雨环流统计模型。同时分析发现:贺兰山东麓暴雨天气70年代发生次数最多,60年代、80年代、90年代、2000年至2006年相对较少;主要发生在每年的春末到秋初,集中出现在7月、8月,其中,7月20日到8月10日为发生高频期,这与宁夏全区大降水主要出现在7月下旬到8月上旬这一发生规律是一致的。灵武到平罗一带为暴雨多发点,平罗发生频次最高,石嘴山市的石炭井发生频次最低。贺兰山大地形对其东麓强降水的发生有明显的增幅作用。 相似文献
832.
C. W. M. Yuen C. W. Kan S. Q. Jiang S. K. A. Ku P. S. R. Choi K. Y. Wong 《Fibers and Polymers》2010,11(2):229-233
This paper is aimed at studying the optimum content of pre-treatment print paste used for ink-jet printing of wool fabric.
Optimum condition of ink-jet printing with respect to the content of pre-treatment print paste and steaming time has been
successfully developed through the orthogonal analysis. The parameters of the pre-treatment print paste including sodium alginate,
urea and ammonium tartrate, as well as the post-treatment of steaming time right after ink-jet printing have been investigated.
The optimum content of the pre-treatment print paste and the proper condition of post-treatment has been developed to achieve
higher colour yield for cyan, yellow, magenta and black color (CYMK). The results of the highest colour yield obtained confirm
that steaming time is the most dominating factor when compared with the other factors. 相似文献
833.
灌溉是灌区农业生产持续发展的先决条件,排水则是决定灌区能否可持续发展的保证。本研究在全面考虑影响灌排系统健康发展的众多因素的基础上,以青铜峡灌区为例,从土壤盐碱化的防治及水资源合理利用角度,运用水盐平衡原理,判别灌区积、脱盐状态及排水效果,分析灌区灌排系统的合理性。分析结果表明青铜峡灌区灌排系统运行良好,对灌区排盐及盐碱化的防治起着积极的作用。同时也发现灌区存在着排灌比过大,排水能力过剩,排水系统不合理等问题。 相似文献
834.
The D-genome progenitor of hexaploid wheat, Aegilops tauschii Coss., has a wide natural species range in central Eurasia and possesses wide natural variation in heading and flowering time. Here, we report identification of two Ae. tauschii accessions insensitive to short day length. Similarly to a loss or reduced degree of vernalization requirement, the photoperiod-insensitive mutations were found only in the early flowering sublineage (TauL1b) of Ae. tauschii. Quantitative trait locus (QTL) analyses using two F2 mapping populations showed that a QTL for heading time on the long arm of chromosome 5D was related to the early heading phenotype of the photoperiod-insensitive accessions under short-day conditions. In the photoperiod-insensitive accession, expression patterns of two flowering-related genes were altered under short-day conditions compared with the patterns in photoperiod-sensitive accessions. This study indicates that analysis of natural variations in the Ae. tauschii population is useful to find novel genetic loci controlling agronomically important traits. 相似文献
835.
为生产抗病转基因绵羊,并确保转基因羊的安全性。克隆绵羊IL-6启动子序列,以IL-6为启动子构建TLR4过表达载体,转染绵羊成纤维细胞验证功能。用1μg·L-1的LPS刺激转染后的绵羊成纤维细胞,利用q PCR技术和ELISA方法检测受LPS刺激后的成纤维细胞TLR4 m RNA表达量和TLR4蛋白表达量。结果表明,转染后的TLR4 m RNA表达量在2、4、24、48 h显著高于对照组(P0.05),其中2、4、24 h极显著高于对照组(P0.01),TLR4蛋白表达量始终高于对照组。说明p IL6-TLR4过表达载体构建成功。 相似文献
836.
Detection of quantitative trait loci for phosphorus deficiency tolerance at soybean seedling stage 总被引:3,自引:1,他引:2
Dan Zhang Hao Cheng Leiyue Geng Guizhen Kan Shiyou Cui Qingchang Meng Junyi Gai Deyue Yu 《Euphytica》2009,167(3):313-322
Phosphorus deficiency is a primary constraint to soybean productivity in acid and calcareous soils. Our aim was to map quantitative
trait loci (QTL) controlling phosphorus deficiency tolerance using 152 recombinant inbred lines derived from a cross between
the P stress tolerant variety Nannong94-156 and the P stress sensitive variety Bogao. Five traits were used as parameters
to evaluate phosphorus deficiency tolerance at seedling stage under different phosphorus levels in experiments 2005 and 2006.
As a result, thirty-four additive QTLs were detected on nine linkage groups, with corresponding contribution ratios of 6.6–19.3%.
There were three clusters of QTL found in genomic regions S506-Satt534 (on linkage group B2-1), Sat_183-Satt274 (on linkage
group D1b + W), and Sat_185-Satt012 (on linkage group G). The locus flanked by Sat_183-Satt274 on linkage group D1b + W was
coincident with four previously discovered QTLs with phosphorus efficiency. Another interesting locus flanked by Sat_185-Satt012
on linkage group G was detected across years. The identified QTL will be useful to improve the stress resistance of soybean
against a complex nutritional disorder caused by phosphorus deficiency. In addition, more QTLs were detected under low phosphorus
condition and some QTLs were detected that specifically expressed under different phosphorus levels. These particular QTLs
could help provide greater understanding of the genetic basis of phosphorus efficiency in soybean. 相似文献
837.
Masahiro Horinouchi Prasert Tongnunui Keisuke Furumitsu Yohei Nakamura Kouki Kanou Atsuko Yamaguchi Ken Okamoto Mitsuhiko Sano 《Fisheries Science》2012,78(3):577-587
To clarify the feeding habits of seagrass fishes, we examined the gut contents from 42 fish species collected in seagrass
habitats in Trang. Thirteen species showed ontogenetic and/or seasonal changes in food-use patterns. Smaller individuals generally
preyed on small planktonic items (e.g., copepod larvae) or small benthic/epiphytic crustaceans (e.g., harpacticoid copepods),
with subsequent changes to other prey items (e.g., shrimps, crabs, detritus and filamentous algae) with growth. The most important
dietary items for the seagrass fish assemblages comprised benthic/epiphytic crustaceans, detritus, and planktonic copepods.
Cluster analysis based on dietary overlaps showed that the seagrass fishes comprised eight feeding guilds (large benthic/epiphytic
crustacean, detritus, planktonic animal, small benthic/epiphytic crustacean, mollusc, invertebrate egg, polychaete, and fish
feeders). Of these, the first three guilds were the most abundantly represented, whereas the last three were each represented
by only a single species. 相似文献
838.
在饲料中分别添加0、0.33%、0.67%、1.33%和2.67%的二苯乙烯苷(THSG)制成5种等氮等能试验饲料饲喂(15±0.5)g斑点叉尾鮰(Ictalurus punctatus)42 d,研究THSG对其生长和体色的影响。结果表明。饲料中添加THSG对斑点叉尾鮰增重率和存活率均无显著影响,仅在添加量为2.67%时,试验组的饵料系数显著高于对照组(P<0.05);然而,随着添加量的增加,鮰皮肤和血液酪氨酸酶活力、皮肤黑色素含量和黑色素分布量均有提高,其中0.33%和0.67%组皮肤中酪氨酸酶活力分别为10.4 U和10.7 U,显著高于对照组的7.86 U;黑色素分布量分别为8.16%和9.38%,显著高于对照组的5.01%(P<0.05)。 相似文献
839.
Ⅱ型单纯疱疹病毒糖蛋白D在杆状病毒表达系统中的表达 总被引:1,自引:1,他引:0
以Ⅱ亚单纯疱疹毒-2333株(HSV-2)的基因组DNA为模板扩增编码HSV-2糖蛋白D(glyco-protein D)基因,与载体pFastBacⅠ连接,转化E.coilDH5α感受态细胞,经PCR及测序鉴定正确。将pFastBacⅠ-gD重组质粒转座至DH10Bac获得重组穿梭质粒,转染Sf9昆虫细胞,获得重组杆状病毒。重组杆状病毒感染Sf9细胞表达重组蛋白,经对表达条件进行优化,SDS-PAGE和Western blot鉴定,成功表达HSV-2 gD蛋白,为下一步的工作奠定了基础。 相似文献
840.
摘要:普惠金融理念注重弱势群体享受金融服务的权利,正在被社会各界所接受。本文从普惠金融视角出发,阐释了当前新型农村金融定位、发展现状与前景、存在的问题与困境,提出了加大农村新型金融机构补贴、建立激励约束机制、构建协调发展机制等建设性政策建议。 相似文献