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71.
山西小杂粮竞争优势与产业发展研究 总被引:7,自引:0,他引:7
tgwgbw@yahoo.com.cn 《中国农学通报》2006,22(5):485-485
(山西农业大学经贸学院,山西太谷 030801) 相似文献
72.
试验材料采用原料场颗粒级配进行缩尺制备,通过大型三轴试验对同一种试样在饱和与干燥的试验条件下进行对比分析,得到干燥试样的内摩擦角大于饱和试样的内摩擦角;且试样的φ0(当围压与大气压比值为1时的妒值)也存在相同的变化规律;干燥试样的颗粒破碎率小于饱和试样的颗粒破碎率;表明对于同一种试样,不同的试验条件对颗粒破碎有一定的影响。 相似文献
73.
本文在刨花静电定向试验的基础上,研究了静电场中刨花极化和定向机理,探索了刨花定向角与电场强度、刨花含水率,刨花形态及极板间距等因素间的相互关系。研究结果表明:一定量的自由离子的存在及其在静电场作用下极化是刨花极化和定向的主要因素;电场强度和刨花含水率对刨花定向程度有显著影响,随着电场强度的增加,平均定向角减小。当电场强度为4KV/cm时,最佳定向角约为19°。 相似文献
74.
Shinji Sasaki Eiji Muraki Yoshinobu Inoue Ryouhei Suezawa Hideki Nikadori Yuuichi Yoshida Shouta Nariai Ryoya Hideshima Shiyunsuke Moriwaki Ryotaro Nakashima Katsuo Uchiyama Kanako Yoshinari Masayuki Takeda Takatoshi Kojima 《Animal Science Journal》2019,90(12):1503-1509
Single nucleotide polymorphism (SNP) arrays are widely used for genetic and genomic analyses in cattle breeding; thus, data derived from SNP arrays have accumulated on a large scale nationwide. Commercial SNP arrays contain a considerable number of unassigned SNPs on the chromosome/position on the genome; these SNPs are excluded in subsequent analyses. Notably, the position‐unassigned SNPs, or “buried SNPs” include some of the markers associated with genetic disease. In this study, we identified the position of buried SNPs using the Basic Local Alignment Search Tool against the surrounding sequences and characterized the relationship between SNPs and genetic diseases in Online Mendelian Inheritance in Animals based on the genomic position. We determined the position of 285 buried SNPs on the genome and surveyed the genotype and allele frequencies of these SNPs in 5,955 individual Japanese Black cattle. Eleven SNPs associated with genetic disease, which contained five buried SNPs, were found in the population with the risk allele frequency ranging from 0.00008396 to 0.46. These results indicate that buried SNPs in the bovine SNP array can be utilized to identify associations with genetic disorders from large scale accumulated SNP genotype data in Japanese Black cattle. 相似文献
75.
PU Lei YUE Jing-wei ZHANG Jin-shan LIU Xin WANG Li-gang YAN Hua HOU Xin-hua GAO Hong-mei ZHANG Tian ZHANG Yue-bo WU Qun-qing ZHANG Long-chao WANG Li-xian 《中国畜牧兽医》2016,43(10):2509-2517
In this study,we cloned MAP3K5 gene cDNA sequence,compared the sequence of MAP3K5 with MAP3K families in pig and other species,and studied their conservative structure domain.Obtained the full-length of MAP3K5 gene (5 452 bp) by RACE-PCR,predicted the open reading frame (ORF) and amino acid (AA) sequence,and obtained the information of 31 exons.The low similarity were found in mRNA and amino acid sequences of MAP3K families in pig (<50%).And MAP3K5 had the comparatively high similarity with MAP3K6 in pig.The comparative analyzed the mRNA and protein sequence of pig MAP3K5 gene with other species MAP3K5 gene,founded that the ten species of MAP3K5 mRNA and protein sequence had the high similarity (>78%),and pig MAP3K5 had the comparatively high similarity with Bos taurus,Ovis aries,Canis lupus and Homo sapiens.Function domain analyzed the high similarity protein with MAP3K5 in pig,this research found that pig MAP3K6 protein had the similar conserved function domain with pig MAP3K5.However,the other pig MAP3K families didn't have the similar conserved function domain with pig MAP3K5.The ten species of MAP3K5 protein had the similar conserved function domain.The results obtained the sequence and molecular structure of MAP3K5 gene,and provided an important foundation for further function research of MAP3K5 gene in pig. 相似文献
76.
77.
《Communications in Soil Science and Plant Analysis》2012,43(7):725-734
Abstract A computer program was developed to calculate bulk density(BD), coefficient of linear extenslbility(COLE), linear extensibility(LE), and linear shrinkage(LS) in the presence or absence of coarse fragments (>2mm). When coarse fragments are present in a soil clod, COLE and linear extensibility calculations become more complex, requiring additional equations and correction factors. The calculation of linear shrinkage is not sensitive to coarse fragments, thus requiring a single equation. This BASIC computer language program is accommodating to various parameter imputs and correction factors for fast calculation of BD, COLE, LE and LS in soil clods with and without coarse fragments. 相似文献
78.
Biomass and production of fine and coarse roots of trees under agrisilvicultural practices in north-east India 总被引:1,自引:0,他引:1
An understanding of the rooting pattern of tree species used in agroforestry systems is essential for the development and management of systems involving them. Seasonal variation, depth wise and lateral distribution of biomass in roots of different diameter classes and their annual production were studied using sequential core sampling. The investigations were carried out in four tree species under tree only and tree+crop situations at ICAR Research Farm, Barapani (Meghalya), India. The tree species were mandarin (Citrus reticulata), alder (Alnus nepalensis), cherry (Prunus cerasoides) and albizia (Paraserianthes falcataria). The contribution of fine roots to the total root biomass ranged from 87% in albizia to 77% in mandarin. The bulk of the fine roots (38% to 47%) in the four tree species was concentrated in the upper 10 cm soil layer, but the coarse roots were concentrated in 10–20 cm soil depth in alder (46%) and albizia (51%) and at 0–10 cm in cherry (41%) and mandarin (48%). In all the four tree species, biomass of both fine- and coarse-roots followed a unimodal growth curve by showing a gradual increase from spring (pre-rainy) season to autumn (post rainy) season. Biomass to necromass ratio varied between 2 to 3 in the four tree species. The maximum (3.2) ratio was observed during spring and the minimum (2) in the rainy season. In alder and albizia, the fine roots were distributed only up to 1 m distance from the tree trunk but in the other two species they were found at a distance up to 1.5 m from the tree trunk. The annual fine root production varied from 3.6 Mg ha–1 to 6.2 Mg ha–1 and total production from 4.2 to 8.4 Mg ha–1 in albizia to mandarin, respectively. Cherry and mandarin had a large number of woody roots in the surface layers which pose physical hindrance during soil working and intercultural operations under agroforestry. But the high biomass of roots of these two species may be advantageous for sequential or spatially separated agroforestry systems. However, alder and albizia have the most desirable rooting characteristics for agroforestry systems.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
79.
本文从曲线半径取值表 ,直线和螺旋线的有关规定以及有关反向曲线和复曲线的一般指南 ,对平面线形设计进行了论述 相似文献
80.
Kazuhiro Aruga 《Journal of Forest Research》2005,10(4):275-284
This article describes a program for optimizing horizontal and vertical alignments of forest roads using Tabu search, a modern heuristic technique. Once a series of intersection points (IPs) is selected manually, the program generates alternative horizontal and vertical alignments. The program precisely generates ground profile and cross sections using a high-resolution digital elevation model (DEM) derived from light detection and ranging (LiDAR) data. It accurately calculates earthwork volumes for curved roadways using the Pappus-based method. The program also estimates construction and maintenance costs. Tabu search optimizes forest road alignments based on the total costs. The application of the program to part of Capitol State Forest in Washington State, USA, indicated that the program successfully found better alignments than manually selected initial alignments. The effect of initial solutions and the number of iterations on the Tabu search process was examined. The result showed that the solutions were improved using the best solutions with the smaller number of grade change points as the initial solutions. It also showed that a small number of iterations could be used to reduce computation time due to the fact that Tabu search is based on a gradient search technique. Finally, the Dijkstra method was examined to find initial solutions without manually initialized solutions. The program, when combined with the Dijkstra method, could find similar-quality solutions from manually initialized solutions. The program will become useful with further tests and verifications. 相似文献