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31.
Industries on the island of Mauritius are under increasing pressure from the regulatory authority and from the general public to control the air pollution from their boilers and particularly that of sulfur dioxide emissions from fuel oil combustion. The measures taken by industry are usually ??ad hoc?? in nature, and there has been yet no proper scientific methodology to justify the nature of the pollution control interventions. Air modeling as a planning tool provides a scientific methodology to industries and to the regulatory authority to select the optimum option(s) among various scenarios such as raising stack heights, changing fuels, implementing cleaner production opportunities or installation of wet scrubbers. The aim of this project was to use an air dispersion model for the selection of air pollution control systems for industrial boilers in an industrial estate. Given a number of constraints on small island developing states like Mauritius, it is recommended to start using established and simple modeling methods, as the complexity of the more refined models requires a relatively long learning curve to be able to use the model correctly. The Industrial Source Complex Short Term (ISCST3) is recommended for that purpose. The application of the ISCST3 model to the multiple-source case study helped in the identification of the most cost-effective options.  相似文献   
32.
 The recovery of population, biomass and reproduction of a dominant crop field earthworm (Drawida willsi, Michaelsen) was assessed following the application of two recommended agricultural doses of malathion (2.2 mg kg–1– single dose and 4.4 mg kg–1– double dose) in a rice field agroecosystem for a period of 105 days. The average worm population and biomass showed 12% and 21% decline, respectively, in plots treated with single and double doses of malathion, compared with control. The peak of worm population was observed after 60 days in control (plot I) and this peak value was shifted by 15 days (i.e. observed after 75 days) in malathion-treated plots (plots II and III) indicating delay in growth and maturation of the worms following the application of malathion. Inhibition in the total number of cocoons produced, and thus in the rate of reproduction, was also observed in malathion-treated plots. The peak rate of reproduction (1.71 cocoons adult–1) was observed after 60 days in control plots and after 75 days (1.57 and 1.40 cocoons adult–1) in single and double dose malathion-treated plots, respectively. One-way analysis of variance showed significant differences in the population size and biomass of D. willsi up to 75 days, in rate of reproduction up to 90 days, and no difference thereafter. This indicates that, under field conditions, D. willsi worms took about 75–90 days after application of malathion to resume normal population, biomass and reproduction, and hence we suggest that a second application of malathion in single and double agricultural doses should be avoided before this time. Received: 7 September 1999  相似文献   
33.
Chloroplast DNA variation in 96 Prunus avium L. cultivars was assessed and compared with the results of a previous study of cpDNA diversity in 23 wild populations of the species. The polymerase chain reaction‐restriction fragment length polymorphism method was used in these studies. Approximately 9% of the chloroplast genome was analyzed, using five universal primer pairs and three restriction enzymes. Ten polymorphic fragments were common to both the wild and sweet cherry; eight polymorphic fragments were found only in the wild cherry. In the cultivars, all mutations were small (5‐30 bp) indels. In the wild populations, a point mutation was also detected in addition to indels. The mutational combinations revealed three haplotypes in the cultivars, which are the main haplotypes in the wild cherry populations. Chloroplast DNA diversity in wild cherry is higher (16 haplotypes) than in sweet cherry cultivars (three haplotypes). The probable wild origin of the sweet cherry cultivars in the maternal line, on the basis of haplotypic similarity, was discussed.  相似文献   
34.
Statistical evaluation of the impact of the SwarnJayanti Gram Swarozgar Yojana (SGSY) on socio-economic development of women in aquaculture in Eastern Hills of Orissa was made. A sample size of 60 women self-help groups (WSHGs) was selected from Koraput and Rayagada districts by multistage stratified random sampling method. The data on socio-economic status of the WSHGs were collected from 2006–2007 to 2008–2009. The members of the WSHGs were interviewed to collect information on their financial contribution and its expenditure pattern. There was a high significant difference between two means in yield (410.9 kg/acre, 306.1 kg/acre), employment generation (387 man-days, 277 man-days), financial contribution by the members to their families (Rs. 3,265/-, Rs. 2,490/-) and expenditure on food (Rs. 953/-, Rs. 538/-) of two groups of WSHGs—the treatment group, i.e., WSHGs under SGSY and the control group. By evaluating the level of development of the WSHGs during 2008–2009, it is revealed that 27.8% of WSHGs under SGSY achieved high level of development in economic sector against 11.9% of WSHGs in the control group. Similarly, in social sector, the percentage of WSHGs in treatment group in the category of high level of development (33%) was higher as compared to the percentage of WSHGs in the control group (11.9%). No significant difference in the development level of empowerment was found between these two groups of WSHGs. The state government should take necessary steps for increasing literacy and technical trainings of the members of the WSHGs in addition to micro-finance for successful implementation of SGSY.  相似文献   
35.
The genetics of resistance to Cucumber mosaic virus (CMV) in Cucumis sativus var. hardwickii R. Alef, the wild progenitor of cultivated cucumber was assessed by challenge inoculation and by natural infection of CMV. Among the 31 genotypes of C. sativus var. hardwickii collected from 21 locations in India the lowest mean percent disease intensity (PDI) was recorded in IC-277048 (6.33%) while the highest PDI was observed in IC-331631 (75.33%). All the four cultivated varieties (DC-1, DC-2, CHC-1 and CHC-2) showed very high PDI and susceptible disease reaction. Based on mean PDI, 8 genotypes were categorized as resistant, 13 as moderately resistant, 9 as moderately susceptible and one as susceptible. A chi-square test of frequency distribution based on mean PDI in F2 progenies of six resistant × susceptible crosses revealed monogenic recessive Mendelian ratio 1(R):3(S) to be the best fit. This monogenic recessive model was further confirmed by 1(R):1(S) ratio as the best fit for back cross with resistant parent and no fit for either 3:1 or 1:1 in the back cross with the susceptible parent. The results revealed that CMV resistance in C. sativus var. hardwickii was controlled by a single recessive gene. Considering the cross compatibility between C. sativus var. hardwickii and cultivated cucumber, the resistance trait can be easily transferred to cultivated species through simple backcross breeding.  相似文献   
36.
Pandanus tectorius Parkinson ( P. fascicularis Lam.) of the family Pandanaceae constitutes one of the major bioresources of Ganjam coast, Orissa; used mainly in small scale perfume industry for aromatic compound extracted from the male inflorescences. In order to establish genetic diversity, if any related to perfume yield, samples of P. tectorius representing male populations from seven locations representing populations I–VII along the coastline of Orissa, India, were analysed for somatic chromosome number, 4C genomic DNA content, randomly amplified polymorphic DNA (RAPD) as well as phytochemicals. The somatic chromosome number in all the populations I–VII was 2n = 60. The chromosomes were of minute size without showing any remarkable structural variation. Like wise the average 4C DNA content was 5.09 pg (≅4,912 Mbp) that showed no intra- or inter-population differences. Out of 54 decamer primers tested, a total of 1,260 amplicons were obtained from 34 primers accounting 43.49% polymorphism. Molecular phylogenetic analysis of the seven populations revealed two distinct branches, with populations II and III in one and the rest populations in the other branch of the phylogenetic tree. It was important to note that the unique populations II and III confined to the Ganjam coast of Orissa having RAPD markers: OPA 09–940 bp, OPA 09–705 bp, OPC 14–1,500 bp, OPC 14–700 bp, OPC 20–1,475 bp, OPC 20–1,350 bp, OPC 20–920 bp and OPC 20–700 bp, were distinguished form the rest of the populations. The aforesaid populations (II and III) are well known to produce aroma of high quality and yield, composed of primarily phenyl ethyl methyl ether (66.8–83%) and terpinen-4-ol (5–12%) along with a number of other phyto-chemical compounds that support the flourishing perfume industry and livelihood of the local people in the region. The findings underscored the possible role of local eco-geography in contributing to the micro-evolution of unique high perfume yielding genotypes of P. tectorius that represented populations II and III at Ganjam coast, which were genetically distinct from the rest of the populations revealed by RAPD analysis.  相似文献   
37.
以生物量与立木蓄积量为基础,对内蒙古通辽市森林生态系统植被碳贮量进行了估算。结果表明:通辽市森林生态系统植被总碳贮量为1 307.03万t,其中,按林种分,用材林、防护林、特用林、疏林、经济林、灌木林、散生木、四旁树的碳贮量分别为:439.42万t、357.35万t、11.53万t、8.94万t、11.12万t、462.70万t、0.74万t、15.23万t;按树种分,杨树碳贮量最大,为680.88万t,占乔木林碳贮量的81.7%;按旗县分,扎鲁特旗森林植被碳贮量最大,为432.56万t,占总碳贮量的32.41%。  相似文献   
38.
An experiment was conducted to determine the performance, antioxidation activity, and bone mineral content in Vanaraja chickens fed diet supplemented with organic trace minerals (oTM) at reduced levels. A total of 360 day-old chicks were selected and distributed randomly into 60 battery brooder pens. A maize–soybean meal-based control diet was supplemented with inorganic trace minerals (iTM), i.e., Mn, Zn, Fe, and Cu at 50, 45, 40, and 7.5 mg/kg, respectively, and varying concentration of oTM, i.e., Zn, Mn, Cu, Fe, I, Se, and Cr at 45, 50, 7.5, 40, 2, 0.30, and 0.25 mg/kg (diet II); 33.75, 37.50, 5.63, 30.0, 1.50, 0.23, and 0.19 mg/kg (diet III); 22.5, 25.0, 3.75, 20.0, 1.0, 0.15, and 0.13 mg/kg (diet IV); 18.0, 20.0, 3.0, 16.0, 0.80, 0.12, and 0.10 mg/kg (diet V); and 13.5, 15.0, 2.25, 12.0, 0.60, 0.09, and 0.08 mg/kg (diet VI), respectively. Each diet was allotted randomly to ten replicates and fed ad libitum from 1 to 42 days of age. The body weight at 14, 28, and 42 days was not affected by reducing the supplementation of oTM concentration in the diets. Similarly, feed intake at 14 days of age was not affected but reduced significantly (P?<?0.05) in the group fed diet IV (50 % oTM) compared to that in the other groups. The higher feed conversion ratio and increased concentration of Ca, P, and trace minerals in tibia were evident in the group fed oTM-supplemented diets compared to the diet containing iTM. Activities of glutathione peroxidase and ferric reducing ability in plasma did not differ in the groups fed on lower concentration of oTM compared to those fed on diet I (control diet). Therefore, it is concluded that the dietary supplementation of trace minerals can be reduced greatly when supplemented as organic form without affecting growth and antioxidant status in Vanaraja chickens.  相似文献   
39.
不饱和聚酯改性松香用于抑制火箭推进剂   总被引:1,自引:0,他引:1  
合成了以丙二醇、邻苯二甲酸和马来酸酐为基料并以松香改性及苯乙烯固化的4种不饱和硬质树脂。讨论了反应条件、用量对产物性能的关系,鉴定其抗热、碱、酸的性能、胶化时间,放热峰温,对水和硝化甘油的吸收。作出作为火箭燃料主抑制剂隔离涂层材料的评价。  相似文献   
40.
歧化松香是一种广泛使用于合成橡胶生产的改性松香。由于酸价高以及其他不理想的性能,歧化松香在涂料领域中的直接使用受到阻碍。本文介绍了以缩水甘油醚为基础制备歧化松香树脂的方法,所制成的树脂可以广泛使用于制油漆、清漆、天然漆以及其它各种用途。这些酯类已制成苯乙烯改性的醇酸树脂而被进一步评价。  相似文献   
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