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1.
1997~1999年对收集引进的22个枣品种进行生长和结果情况调查及物候期定点预测,以大荔圆枣为对照,从丰产性、品质、抗性(抗裂果)、单果重、结果整齐度5个方面进行综合评比,筛选出适宜我省发展的不同用途的枣树优良品种12个,为黄土高原红枣产业化发展提供了品种依据。  相似文献   
2.
Landscape modeling requires the delineation of system boundaries and interior features. Quite often, these components are complex and difficult to accurately represent. A rectangular grid is used to represent the study and adjacent non-study areas in most cases. When the non-study area occupies a large portion of the grid, computer memory is wasted, and computational time increases. An elliptical grid generator for non-orthogonal curvilinear coordinates is used to generate a boundary-fitted grid for a landscape model. In a boundary-fitted grid coordinate system, one coordinate axis follows the landscape domain boundary and is non-orthogonal to the second axis. The boundary-fitted grid uses elliptic partial differential equations to distribute grid points inside the landscape domain. Although the boundary-fitted grid follows the domain boundary, the grid pattern and point allocation remain structured. Thus, a landscape model can use a boundary-fitted grid without changing the model’s data structure or the computational scheme. In this study, a boundary-fitted grid and a raster-based grid were applied to the Everglades Landscape Fire Model. Use of the boundary-fitted grid decreased model simulation time by about one fifth and computer storage by 58% relative to the raster-based grid. Also, the linear characteristics of interior geographical features such as rivers and airboat trails were preserved by the boundary-fitted grid, but not by the raster-based grid. This preservation provided a more reasonable base map for simulating ecological processes, such as fire across heterogenous landscapes.  相似文献   
3.
模糊评分法在高羊茅品种综合评价中的应用   总被引:3,自引:1,他引:2  
1999--2001年对引进和培育的高羊茅新品种(系)在喀斯特生态区进行品种比较试验。观测记裁各参试品种的性状表现,对春、夏、秋、冬4个季节的观测结果,用模糊评分法Ⅲ进行分析比较,并按综合评价值的大小排序a结果高羊茅“98--1”的综合评价值最大,排第一名,依次是猎狗5号、矮星2号、凌志(对照),其余参试品种排名次后。认为用模糊评分法对高羊茅品种进行分析评价是可行的。  相似文献   
4.
本文讨论一类三阶时滞泛函微分方程解的渐近性质,给出了若干解的有界性及解趋于零的判定准则.  相似文献   
5.
采用二次微分的方法,得到了角形区域Ω1的Affine变换关于其边界值不是极值映照.并明确给出在边界同伦下唯一极值的Teichmuler映照.  相似文献   
6.
中层拖网的水层控制   总被引:2,自引:0,他引:2  
  相似文献   
7.
干椒1号是由母本二金条-12-6-4和父本羊角-2-3配制的一代杂交种。该品种早熟,高抗病毒病、疫病,耐寒、耐热、耐湿、耐瘠。果实细长羊角形,青椒绿色,老熟果鲜红色,果皮薄、籽少、味辣,易脱水,晒干率高,宜作晒干椒或鲜食。一般667m^2产鲜红椒2500kg,或干椒800kg。全国各地均宜种植,特别适宜嗜辣、习惯晒干椒的地区大面积推广。  相似文献   
8.
黄麻(新、引进)品种在闽南地区的产量(鉴定)试验   总被引:2,自引:0,他引:2  
洪建基  曾日秋 《中国麻业》2006,28(3):128-132
通过对中国农科院麻类所新选育的3个黄麻圆果种和12个国外引进的黄麻优异品种进行2002-2005年品种比较试验,结果表明:C90-2、C90-6、C89-6比对照种粤圆五号增产14.97%-19.34%,均达极显著水平。O-3、O-1、O-3(红茎)比对照种宽叶长果增产32.02%-34.21%,均达极显著水平。O-4(Ⅱ)比对照种增产12.28%达显著水平。C-1、C-5比对照种粤圆五号增产11.90%和7.82%。且主要经济性状优良,抗病力强。黄麻品种C90-2、C90-6、C89-6、O-3、O-1、O-3(红茎)、0-4(Ⅱ)、C-1和C-5适合于福建闽南麻区推广种植。  相似文献   
9.
研究了一类时滞微分系统解的渐近性态.在一些比已有文献通常附加的局部李普希兹条件更弱的条件下,证明了此系统的每个有界解趋于某平衡态.我们的结果推广了已有的一些结论.  相似文献   
10.
Generally accepted criteria were used to identify typical nucleated thrombocytes and typical small lymphocytes in chicken-blood smears subjected to modified-Wright staining. Other cells, here referred to as "intermediate cells," were difficult to classify because in some aspects they resembled thrombocytes while they also had features typical of small lymphocytes. The "intermediate cells" had small, round or oval nuclei with coarsely condensed chromatin, characteristic of both thrombocytes and small lymphocytes. In addition, "intermediate cells" had moderately abundant cytoplasmic volumes, typical of thrombocytes but blue cytoplasm lacking both granules and vacuoles, which is characteristic of small lymphocytes. It made little difference to the thrombocyte count whether these cells were classified as thrombocytes or small lymphocytes; however, this decision made a substantial difference to the lymphocyte count in some chicken-blood smears. Most "intermediate cells" (351 of 410 cells examined) were nonfluorescent after treatment with formaldehyde gas. Furthermore, most "intermediate cells" failed to acquire characteristic pigments when subjected to either Grimelius staining (179 of 204 cells examined) or periodic acid-Schiff staining (173 of 206 cells examined). Typical small lymphocytes reacted in the same way, failing to fluoresce after gaseous formaldehyde treatment (65 of 65 cells examined) and failing to react during Grimelius staining (41 of 44 cells examined) or periodic acid-Schiff staining (21 of 21 cells examined). In contrast, almost all typical thrombocytes became fluorescent in response to gaseous formaldehyde (709 of 718 cells examined) and gave positive reactions when subjected to Grimelius staining (381 of 382 cells examined) or periodic acid-Schiff staining (322 of 326 cells examined). These findings suggested that "intermediate cells" should be classified as lymphocytes in differential cell counts.  相似文献   
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