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1.
MATLAB软件在数据处理中的应用   总被引:5,自引:0,他引:5  
通过MATLAB软件在土工试验数据处理方面应用过程的探索,介绍一种新型的数据处理软件,为今后的试验数据处理提供一种新的思路。  相似文献   

2.
Surfer软件在农田防护林网研究中的应用   总被引:5,自引:0,他引:5       下载免费PDF全文
 为从空间上研究农田防护林网的防护作用范围,利用Surfer软件强大的等值线与三维图形绘制功能,以及用空间数据的形式表达区域内各因子分布格局的特点,通过用Surfer对野外数据进行分析的实例说明该软件的成图过程,并通过与以往方法的比较得出Surfer软件在数据制图与分析方面的优势。结果表明,该软件能够在很大程度上促进农田防护林及水土保持相关领域的研究,具有很强的应用前景。  相似文献   

3.
世界粮食研究模型在黑龙江省作物产量预报中的应用   总被引:6,自引:5,他引:6  
在现有研究成果的基础上,提出世界粮食研究(WOFOST)模型在黑龙江省四大作物产量预报应用中的参数分区处理方法,运用WOFOST的模拟产量和趋势产量对黑龙江省四大作物产量进行了预测分析。研究表明:该方法效果理想、可行,具有理论研究和实际应用价值,克服了只用一组参数在复杂气候区域进行作物产量模拟的局限性,拓宽了WOFOST模型在复杂气候条件下的应用领域。  相似文献   

4.
137Cs在耕作土壤中的均一性分布研究   总被引:2,自引:0,他引:2  
王小雷  杨浩  桑利娟  刘晓海  赵其国 《土壤》2009,41(6):897-901
选择一块面积为35m×30m较为平坦的农耕地作为研究对象,采集68个样点,共计112个样品,对~(137)Cs在土壤中的垂直分布和水平分布进行了探讨.结果表明,~(137)Cs在耕作土壤剖面中分布主要集中在耕层以内,且各个层的质量活度介于2.92~4.01Bq/kg之间,在土壤表层中水平面上质量活度介于28.77~30.98Bq/kg之间,该核素在土壤剖面和地表水平面上都呈现均一性分布特征.  相似文献   

5.
辣椒素类物质在烤制加工和储藏中的稳定性   总被引:1,自引:1,他引:1  
为了解辣椒素类物质在烤制加工和储藏过程中的稳定性,该文研究了不同加热温度和时间处理以及不同储藏条件下(常温和冷藏,真空和非真空),野山椒中辣椒素类物质的含量变化。试验结果表明:烤制加热温度(80~180℃)及其时间(2~16 min)对辣椒素类物质的影响均显著(p<0.01);不同储藏条件下,随着储藏时间的延长,野山椒中辣椒素类物质的含量均有不同程度下降。9个月后,真空包装冷藏的辣椒粉中辣椒素类物质含量降低了16.44%,非真空包装冷藏的降低了17.00%,真空包装常温储藏的降低了23.58%,非真空包装常温储藏的降低了24.11%,真空包装对其稳定性影响不大,低温更有利于保存辣椒素类物质。  相似文献   

6.
核糖核酸酶(Ribonucleases,RNase,RNS) T2普遍存在于各种生物中,其保守性提示了功能的重要性.在水稻基因组中有8个RNase T2成员,本试验采用基于抗体的蛋白质组学策略,用免疫印迹(Western Blotting,WB)技术检测了它们在叶片生长及盐胁迫条件下的表达,发现OsRNS1-OsRNS7蛋白质在叶片中有表达,其中OsRNS4主要在苗期表达,提示其在苗期发挥作用,其它蛋白质主要在成株期表达,但没有检测到OsRNS8的表达;水稻OsRNS4在盐胁迫条件下表达上调,提示其可能在盐胁迫应答过程中发挥作用,其它RNase T2蛋白质的表达大多随盐胁迫时间的延长而下降.将RNase T2蛋白质的表达与转录信号进行比较,发现二者在部分基因中有一定的相关性.本试验获得的数据为揭示水稻RNase T2基因的功能提供了线索.  相似文献   

7.
CDK1和CyclinB1在不同月龄绵羊睾丸中的表达与定位   总被引:1,自引:0,他引:1  
哺乳动物精母细胞减数分裂至成熟受蛋白依赖性激酶(cyclin-dependent kinase,CDK1)和细胞周期蛋白B(CyclinB1)形成的复合物细胞促分裂因子(maturation promoting factor,MPF)控制.本实验选取0、2、6、12和24月龄绵羊(Ovis aires)睾丸组织,探究了不同月龄绵羊睾丸中CDK1和CyclinB1表达与定位情况.通过qRT-PCR方法检测了CDK1和CyclinB1在不同月龄绵羊睾丸中mRNA表达情况,并利用免疫组织化学染色技术对睾丸组织中CDK1和CyclinB1蛋白定位.结果表明,绵羊睾丸中CDK1和CyclinB1 mRNA表达量随月龄的增加呈现先下降后上升的趋势.CDK1和CyclinB1蛋白在细胞中主要定位于精原细胞、初级精母细胞和次级精母细胞.各发育期CDK1蛋白表达量均低于CyclinB1蛋白的表达量,其中CDK1蛋白在整个细胞周期中表达量极少且相对稳定,CyclinB1蛋白在各发育期表达量不同.说明CDK1和CyclinB1 mRNA和蛋白质在不同月龄绵羊睾丸中的表达量存在一定差异,可能对绵羊睾丸发育有一定的调节作用.  相似文献   

8.
ATP结合盒(ATP-binding cassette,ABC)转运蛋白是一类普遍存在于真核和原核生物细胞中的超家族转运蛋白,在生理活动中发挥着重要作用.本文较为详细地介绍了其结构特点,并按保守区进化关系进行了分类,分成A~H 8个亚族;归纳了近年来有关ABC转运蛋白在提高植物和真菌重金属耐性作用的研究报道,并从液泡区隔作用、直接外排作用和线粒体ABC转运蛋白重金属转运作用3个方面对其提高宿主重金属耐性作用机制进行了总结和分析,提出了ABC转运蛋白转运金属离子选择偏好性的观点,同时对ABC转运蛋白进一步的研究和潜在的应用提出了展望.  相似文献   

9.
Bowman-Birk胰蛋白酶抑制剂(BBTI)是一类富含半胱氨酸的丝氨酸蛋白酶抑制剂,广泛分布于豆科、禾本科和菊科植物中,在蛋白质存储和植物防御中具有重要作用。水稻(Oryza sativa L.ssp.indica)BBTI家族具有13个成员,其中BBTI-9和BBTI-10都为假基因。其余BBTI成员都存在数量不同的保守Bowman-Birk结构域。为了解BBTI的表达信息,本研究主要通过设计多肽序列的方法,制备了11个BBTI的多克隆抗体,利用Western blot技术检测其在叶片生长发育和种子萌发过程中的表达。结果表明BBTI在叶片生长过程中呈现不同的时空特异性表达,BBTI-1、-2、-11、-12和-13伴随叶片生长含量增加,BBTI-5、-6和-8在苗期表达含量高,而BBTI-3、-4、-7在苗早期1cm时表达量达到峰值,以修饰或多聚体的形式在叶片生长过程中表达。在种子萌发过程中发现BBTI-8在种子中表达量较高,萌发后2h降到最低,24h后一条分子量略小的降解带开始表达,其余抗体在种子萌发阶段未发现有明显的变化。本研究还统计了苗期叶片、分蘖期叶片和萌发期的种子的MPSStags数据,试图比较转录与蛋白质水平对应关系。本研究结果证明,BBTI蛋白质在水稻生长发育过程中存在差异表达,为深入了解其功能提供了重要线索。  相似文献   

10.
11.
The relationship between nitrogen fixation and the numbers of cyanobionts and heterocysts in the mature leaves of fifteen Azolla strains from five species was examined. The nitrogenase (acetylene reduction) activity per leaf and the numbers of cyanobionts and heterocysts in the mature region varied depending on the Azolla strains. The numbers of cyanobionts and heterocysts, particularly the number of heterocysts, were closely correlated with the nitrogenase activity per leaf. However, the nitrogenase activity per leaf was not correlated with the nitrogenase activity per heterocyst. The results indicate that the variation in the nitrogenase activity of the leaves among Azolla strains mainly resulted from the variation in the number of heterocysts and not from the variation in the nitrogenase activity per heterocyst.  相似文献   

12.
13.
The biodegradation of polycyclic aromatic hydrocarbons (PAHs) via free-living and attached micro-organisms in soil/water systems was observed in order to examine the variability in the community dynamics and physiological profiles of the micro-organisms. As determined by fluorescence in situ hybridization (FISH), the Domain Bacteria, consisting of three phyla α-, β- and γ-Proteobacteria, reached 41.27–56.05% of all organisms in the soil/water system for PAH biodegradation. Among the free-living species, Proteobacteria, including Brevundimonas (Pseudomonas) diminuta, Caulobacter spp., Mycoplana bullata, Acidovorax spp. and Pseudomonas aeruginosa were found to be dominant—making up 93.51–99.80% of the population—and therefore seem to be associated with PAH biodegradation. Total plate count numbers and the count of Pseudomonas sp. present in the free-living population increased to between 103 and 106 CFU ml−1 when clay with very low organic matter content was used as the matrix for PAH degradation. However, total plate count microbial numbers increased to only 101–102 CFU ml−1 using natural soil from Taichung containing 1.883% organic matter. The soil organic content (SOM) seemed to affect the mass transfer of PAH in soil, leading to the difference in PAH biodegradation. Two different approaches, which included community-level physiological profiling (CLPP) and ectoenzymatic activities, were used to explain the functional diversity between free-living and attached bacteria. The free-living and attached bacterial communities from the clay system showed proportionately greater differences using CLPP. Relatively high levels of esterases, aminopeptidases and some specific glycolysis-gluconeogenesis enzymes gave an identifiable correlation with PAH biodegradation. The differences in bacterial composition, numbers and physiological characteristics show that free-living and attached micro-organisms may play different biochemical roles in PAH degradation in soil.  相似文献   

14.
为探索不同耕地集约利用水平下的碳排放效率变化规律,更好实现耕地集约利用的社会效益和生态效益,该文分别构建了耕地集约利用模型和数据包络分析模型,运用GIS(geographic information system)空间分析技术分析了河北省138个县(市)耕地集约利用度和耕地碳排放效率时空变异特征,在此基础上探索了耕地集约利用与碳排放综合效率的空间聚集差异特征。研究结果表明:河北省耕地集约利用水平呈现由平原区向山地丘陵再向坝上高原区扩展的趋势;碳排放综合效率有效区域集中分布于坝上高原与山地丘陵区,而石家庄、邢台和经济发展较好的唐山等地区碳排放综合效率较低;耕地集约利用度和碳排放综合效率空间分布上总体呈现负相关性,且随着时间推移局部聚集效应呈现不断增强的态势。  相似文献   

15.
准确评价汞(Hg)在土壤中的有效性对预测污染土壤中Hg的潜在生态风险及其环境质量标准的修订具有十分重要的意义。本研究通过稳定同位素202Hg稀释技术及同位素交换动力学方法(IEK)分析红壤和潮土中同位素可交换Hg含量(E值)及同位素可利用态Hg含量(Ea),并与4种单一提取法和1种连续提取法(改进的BCR法)获得的土壤有效态Hg含量进行比较。结果表明,外源稳定同位素202Hg加入土壤后,红壤和潮土的悬浮液中同位素交换均在24 h后达到稳定状态。同位素交换动力学方程对悬浮液中同位素比值及土壤同位素交换态含量Et值的变化有比较理想的拟合效果,红壤三个间段的E值(E1 min、E1 min-24 h和E24 h)及所占全量的比例均高于潮土。两种土壤Ea(为E1 min与E1 min-24 h之和)所占全量的比例为38%~60%,显著高于单一提取法中提取率最高的0.03%TGA-1/15 mol L-1Na2HPO4(10%~15%)及连续提取的∑BCR(20%~27%,为酸可提取态、还原态和氧化态占全量之和),这表明与化学方法相比较,用土壤同位素可利用态Hg含量(Ea)作为土壤中有效态Hg含量的表征可能偏高,原因可能与外源同位素被土壤固持及土壤悬浮液的性质有关。  相似文献   

16.
In 1999, the Russian Federation created a Tiger Response Team (TRT) to investigate and intervene in human–tiger conflicts. We examined data collected on human-Amur tiger (Panthera tigris altaica) conflicts from January 2000 through February 2009 to: (1) summarize and characterize human–tiger conflicts in the area, (2) examine causes of human–tiger conflicts, and (3) attempt to evaluate the effectiveness of the TRT. The team investigated 202 conflicts. Both attacks on humans and depredations were greatest in winter (X2 = 9, df = 3, P = 0.03 and X2 = 64, df = 3, P < 0.001, respectively). Tiger depredation on domestic animals was the most common type of conflict reported (57%), followed by tigers near human habitations (22%), miscellaneous conflicts (12%), and attacks on humans (9%). Dogs were killed more commonly than other domestic animals (63% of 254 animals), likely because livestock were well managed. Nineteen attacks on humans were recorded resulting in 11 injuries and 2 deaths. Nearly four tigers per year (n = 32 tigers) died, were killed, or were removed from the wild, and all but 1 of 20 tigers killed or removed from the wild by the TRT were considered unfit to survive in the wild. Attacks on humans (n = 19) were most often (77%) by wounded tigers (80% of injuries were human-caused) and commonly provoked (47% of attacks). The effectiveness of interventions focused on reducing depredation on domestic animals was unclear, but data suggested that removal of injured and other unhealthy tigers from the wild by the Tiger Response Team resulted in fewer human deaths. Our recommendations include that the TRT continues to work to reduce conflict by rapidly removing debilitated tigers from the wild, explores different methods and technologies for reducing depredation on domestic animals, and increases their efforts to maintain tigers in the wild through telemetry monitoring, translocation, and rehabilitation of orphaned cubs. Further, standardized data should be collected to evaluate all interventions, with information from evaluation guiding an adaptive management component of their human–tiger conflict mitigation activities. This process should occur across tiger landscapes in Asia to allow rapid assessment of interventions.  相似文献   

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