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11.
The moisture transport expressed with wicking is one of the most important aspects in clothing science and strongly effects on the quality of clothes. Wicking is a spontaneous transport of liquid driven into a porous system by capillary forces. Furthermore, the packing density has a direct relation with the yarn structure. At the present work, the effects of yarn count and twist factor on the wicking height and packing density of lyocell ring-spun yarns was investigated. Achieving the objectives of this research, an image processing method was developed to determine the packing density of samples. Experimental results were also used to develop a regression model to predict the wicking height based on the packing density, yarn count, twist factor and rising time. The results demonstrated that the correlation coefficient between the predicted and measured wicking height was 0.98 indicating the capability of the presented model to predict the wicking height of lyocell ring-spun yarns. 相似文献
12.
One of the most important elements affecting the growth and development of a plant is salinity. Therefore, to evaluate the
effect of salinity on some physiological aspect of Strawberry (Fragaria x ananassa Duch.) plants cv. Camarosa, a greenhouse
experiment was conducted at Vali-e-Asr University of Rafsanjan in 2009. This study was carried out as Factorial experiment
based on RCD design with 4 replications to determine the influence of salinities (0, 30, 60 and 9 mMol.L-1) on proline, soluble
sugars content, chlorophyll a (CHLa), chlorophyll b (CHLb), total chlorophyll (TC), Spad and chlorophyll florescence. Results
indicated that fresh leaves tissue were used to measure proline, soluble protein and soluble sugars content, CHLa, CHLb, TC.
Salinity treatment significantly increased proline content, soluble sugars while chlorophyll a (CHLa), chlorophyll b (CHLb),
Spad and chlorophyll florescence significantly decreased. Nine day after NaCl exposure, Fv/Fm and Spad in 60 and 90 mM NaCl
were significantly lower than control. It was concluded that this cultivar of strawberry may uses osmoregulation by increasing
proline and soluble sugars level in order to tolerate salinity conditions. 相似文献
13.
14.
Omid Khalifezadeh Koureh Mohammadreza Pourghayoumi Majid Majidian 《International Journal of Fruit Science》2019,19(1):1-12
The aim of this research was to determine the effect of three different fertilizing systems, including organic, conventional, and integrated ones, on the yield, fruit quality, antioxidant activity, and some phenolic compounds of white seedless grape. The study was carried out on several 6-year-old white seedless grapevine located in the Urmia Province (North-West Iran). The results showed that the fruit physical characteristics and yield were affected significantly by different fertilization systems. The highest yield was observed in the conventional fertilization, followed by organic and integrated systems. The leaf mineral contents were obviously dependent on the different fertilization used, whereas pH and titratable acidity were not affected. Based on our results, the highest values of antioxidant activity and total flavonoid were found in the organic and integrated fertilization systems, respectively. Also, the highest contents of total phenolic, catechin, and quercetin-3-galactoside were observed in the organic fertilization system. Overall, the highest nutritional quality and biochemical characteristics of white seedless grape were obtained in organic fertilization system, which improved antioxidant capacity by enhancing total phenolics, total flavonoids and valuable phenolic compounds. 相似文献
15.
A survey of ovine schistosomiasis was carried out in a Schistosoma bovis enzootic area in the central Sudan. Three hundred Desert sheep, representing different age groups, were screened for infection, using Pitchford's faecal egg counting technique. No infection was detected in animals under one year old, but from the age of 18 months onward, the prevalence increased progressively from around 20 per cent to 60 per cent in six-year-old sheep, and this was accompanied by an increase in infection intensity, as determined by faecal egg counts. These findings, which suggest that these sheep did not develop an effective resistance to schistosomiasis, contrasted with those previously recorded in cattle from the same locality, studied in the same year. 相似文献
16.
Fatemeh RAJAEI Abbas E SARI Abdolrassoul SALMANMAHINY Timothy O RANDHIR Majid DELAVAR Reza D BEHROOZ Alireza M BAVANI 《干旱区科学》2018,10(3):457-469
Conversion of forest land to farmland in the Hyrcanian forest of northern Iran increases the nutrient input, especially the phosphorus(P) nutrient, thus impacting the water quality. Modeling the effect of forest loss on surface water quality provides valuable information for forest management. This study predicts the future impacts of forest loss between 2010 and 2040 on P loading in the Tajan River watershed at the sub-watershed level. To understand drivers of the land cover, we used Land Change Modeler(LCM) combining with the Soil Water Assessment Tool(SWAT) model to simulate the impacts of land use change on P loading. We characterized priority management areas for locating comprehensive and cost-effective management practices at the sub-watershed level. Results show that agricultural expansion has led to an intense deforestation. During the future period 2010–2040, forest area is expected to decrease by 34,739 hm~2. And the areas of pasture and agriculture are expected to increase by 7668 and 27,071 hm~2, respectively. In most sub-watersheds, P pollution will be intensified with the increase in deforestation by the year 2040. And the P concentration is expected to increase from 0.08 to 2.30 mg/L in all of sub-watersheds by the year 2040. It should be noted that the phosphorous concentration exceeds the American Public Health Association′s water quality standard of 0.2 mg/L for P in drinking water in both current and future scenarios in the Tajan River watershed. Only 30% of sub-watersheds will comply with the water quality standards by the year 2040. The finding of the present study highlights the importance of conserving forest area to maintain a stable water quality. 相似文献
17.
Genetic analysis of late blight resistance in Solanum pimpinellifolium accession PI 270441: Heritability and response to selection 下载免费PDF全文
Late blight (LB), caused by Phytophthora infestans, is a destructive disease of tomato (Solanum lycopersicum) worldwide. Currently, there are few commercial cultivars of tomato with resistance to LB, and the disease is mainly controlled by heavy use of fungicides. Due to the emergence of fungicide‐resistant pathogen isolates, there is a concerted effort to identify new genetic sources of resistance and breed new resistant cultivars. A recent screening identified several new tomato accessions with strong resistance to LB. Here, we report on the genetic basis of LB resistance in S. pimpinellifolium accession PI 270441, as determined by generation means analysis and analysis of response to selection, using populations derived from crosses with LB‐susceptible breeding line Fla. 8059. Heritability of LB resistance ranged from 0.76 to 0.78, and the minimum number of genes was estimated 1—few. These results suggest that transfer of LB resistance from PI 270441 to the cultivated tomato should be feasible via a traditional backcross breeding approach. Genetic mapping studies are underway to identify molecular markers associated with resistance in this accession. 相似文献
18.
Zeinab Mirzaie Fouladvand Ebrahim Pourjam Natsumi Kanzaki Robin M. Giblin‐Davis Majid Pedram 《Forest Pathology》2019,49(2)
Basilaphelenchus gorganensis n. sp. is described and illustrated from wood and bark of a dead tree from northern Iran. The new species is characterized by female body length (415–559 µm), three‐lined lateral fields, a sclerotized cephalic vestibule and cephalic framework, thin stylet with three elongate backwardly directed knobs, small spherical to oval metacorpus, with small and posteriorly located valve, simple vulva without any flap apparatus, 59‐ to 79‐µm‐long post‐vulval uterine sac, functional rectum and anus and dorsally convex, ventrally concave, usually ventrally bent conical female tail with a sharp tip. Males are common, apparently functional and characterized by well‐curved spicules, three pairs of small caudal papillae and no bursa at tail tip. Molecular phylogenetic inferences using partial sequences of small and large subunit ribosomal RNA genes (SSU and LSU rDNA) from different isolates of the new species revealed it differs from currently sequenced species and belongs to the Tylaphelenchinae clade. 相似文献
19.
In our investigation we studied fiber lengths and the transition age from juvenile to mature wood in Acer velutinum Boiss. For this purpose, samples from three normal maple trees at a Noshahr site in northern Iran were selected. Disks were cut at breast height. Test samples were taken along a radial direction from the pith to the bark, accounting for every ring during a 48-year period. We used the Franklin method to distinguish between fibers of juvenile and mature wood. The results show that the fiber length increased along the radial direction from the pith to the bark. The transition age between juvenile and mature wood was determined at the 14th annual ring from the pith. 相似文献
20.
A. H. Shoga'a Aldeen N. M. Majid A. M Azani Awang Noor Abd. Ghani Shukri Mohamed 《Journal of Sustainable Forestry》2013,32(3):286-309
Yemen is one of the world's least developed countries and experiences problems of scarcity of natural agricultural resources as well as soil erosion and degradation. Agroforestry systems (AFS) are being promoted as a more appropriate land use system than monocropping systems (MCS) worldwide. Unfortunately, long-term studies on agroforestry and other land use systems (LUS) do not exist in Yemen. Agroforestry in the Rima'a region has started to deteriorate and many farmers turned to (MCS). This study was conducted in the Rima'a Valley, near Alsharq town, Dhamar, Yemen. The study evaluates the soil nutrients, organic matter (OM), and other soil properties such as pH, bulk density, and porosity under AFS and compares it with soil under MCS. Standard procedures for soil sampling and analyzing were used to collect and analyze 36 composite samples from Site 1 and 36 composite samples from Site 2 from six cropping systems (treatments). The results showed that there were significant variations in relation to LUS. Agroforestry practices—mixed trees with coffee (S1), and Cordia africana L. with coffee (S2) have higher nitrogen concentration (0.17–0.26%) as compared to the Ziziphus spina-christi L. with maize (S3) and the monocropping maize (S5), (<0.16% in both Sites 1 and 2). Similar results were seen on the effect of the different LUS on the soil P, K, and OM contents at the two sites (p < .01). While soil N, P, and soil K were higher under agroforestry systems S1, and S2 in both sites, it was the lowest in S5 in both sites. It can be concluded that agroforestry has more favorable effects on soil fertility and other soil properties. The government should establish programs and campaigns to disseminate AFS technology and promote the importance of agroforestry in soil conservation. 相似文献