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131.
Mariane Alves de Godoy Leme Miriam Gonçalves Miguel 《Water, air, and soil pollution》2018,229(11):374
In many developing countries, a landfill remains one of the most extensively employed solid waste disposal solutions. Although a landfill is a well-designed engineering system, the base lining of a landfill may perform poorly and allow the leachate to reach the underlying soil layers and groundwater. Leachates contain a variety of toxic and hazardous contaminants, which are attenuated in the soil by various processes that slow or transform them. Thus, the objective of this research was to study the water and leachate permeability and retention of the liner soil in a landfill experimental cell by subjecting it to geotechnical, chemical-mineralogical, and physicochemical characterizations, water and leachate permeability tests, and mercury intrusion porosimetry (MIP). In addition, the water and leachate retention curves were determined and analyzed using RETention Curve (RETC) software to obtain the unsaturated permeability curves. The leachate in the soil decreased the suction considering the moisture content of the compacted soil in the field, which consequently increased the leachate permeability of the mineral liner. For the same suction value, in the drying pathways, the soil retained a greater amount of distilled water than leachate. In the wetting pathways, the opposite occurred. Microorganisms were detected in the soil during the filter paper test. The permeability coefficients of the unsaturated soil were directly proportional to the gravimetric moisture content for the water and the leachate, which demonstrated that the soil presents lower unsaturated permeability coefficients for water than for leachate for the same water content. 相似文献
132.
K. R. S. Ascher Miriam Eliyahu E. Glotter I. Kirson A. Abraham 《Phytoparasitica》1984,12(3-4):147-155
The geographical distribution of the chemotypes ofWithania somnifera Dun. (Solanaceae) in Israel was re-investigated. In the distribution area of chemotype II (major steroidal constituent, withanolide D), plants of chemotype III (major steroidal constituent, withanolide E) were also found. The antifeedant properties forSpodoptera littoralis larvae of leaves ofW. somnifera populations belonging to chemotype III are due to the presence of withanolide E and may be used, as a supplement to chemical analysis, to differentiate between chemotype III and other chemotypes ofW. somnifera. 相似文献
133.
134.
S-31183 was assayed against preimaginal stages of the tobacco whitefly,Bemisia tabaci (Genn.), and eggs of the Egyptian cotton leafworm,Spodoptera littoralis (Boisd.). The compound was found to be an ovicide forB. tabaci eggs in both preinfestation and postinfestation treatments. FreshS. littoralis eggs were very susceptible to the compound at 0.05 ppm a.i., response was much poorer with 1-2-day-old eggs and 2-3-day-old
eggs were not affected even by 100 ppm.
Publication of the Agricultural Research Organization. No. 2271-E, 1988 series. 相似文献
135.
Mara de Menezes Assis Gomes Eliemar Campostrini Nilton Rocha Leal Alexandre Pio Viana Tiago Massi Ferraz Luciane do Nascimento Siqueira Raul Castro Carriello Rosa Alena Torres Netto Miriam Nuñez-Vázquez Marco António Teixeira Zullo 《Scientia Horticulturae》2006
The effects of successive brassinosteroid analogue (BR) applications (0.1 mg l−1 of brassinosteroid analogue BB-16) were evaluated on commercial yellow passion fruit (Passiflora edulis f. flavicarpa) orchards in the first year of production. The treatments applied were: control, BR-1 (1 BR application shortly after the first flowers appeared), BR-2, BR-3, BR-4 and BR-5 (BR application in two, three, four and five consecutive weeks after the appearance of the first flowers, respectively). The fruits were collected for seven consecutive weeks (105 fruits treatment−1) and fruit mass, length and diameter, soluble solid contents; pulp mass and peel thickness were evaluated in the laboratory. Multivariate analysis was performed in order to determine whether there were differences among the treatments taking into account all the measurements made. BR-3 was the most promising treatment because it produced the highest number of fruits plant−1 (81.5) compared to the control (53.5) and the soluble solid content was 1 °Brix greater than the control. The BR-3 treatment resulted in a 65% increase in the estimated yield of the passion fruit plants, corresponding to 20 t ha−1 compared to the control yield of 12 t ha−1. The results showed that BB-16 sprayed during a period of reproductive development can increase the number of fruits per plant. 相似文献
136.
Propylene oxide (PPO) was evaluated at a low pressure of 100 mm Hg for toxicity to different life stages of the Indianmeal
mothPlodia interpunctella (Hübner) in the presence and absence of three species of nuts. Eggs and larvae were generally the most tolerant life stages
in empty chambers and on the nut crops. Complete mortality of all life stages was achieved at a concentration x time (CT)
product of 61.2 mg hl
−1 for empty space fumigation. Dosages of 13.9, 60.3, 72.1 and 93.1 mgl
−1 were required to kill 99% of the larvae when fumigation of 4-h duration took place in an empty chamber and in the presence
of peanuts, almonds and walnuts, respectively. After an initial dose of 68.7 mgl
−1 and a 5-h exposure time, sorption of PPO by peanuts, almonds and walnuts was relatively high, ranging from 87% of the initial
concentration for peanuts to 91% for walnuts. PPO residues measured in peanuts, almonds and walnuts were 111, 46 and 80 ppm,
respectively, 1 day after termination of fumigation. All of these values were below the 300 ppm maximum tolerance set by the
FDA of the United States. These data show that the combination of PPO and low pressure has the potential to replace methyl
bromide fumigation for quarantine and pre-shipment purposes.
http://www.phytoparasitica.org posting July 22, 2006 相似文献
137.
Heat treatment of dates at the time of harvest, was examined as an alternative to fumigation with methyl bromide, which has
been phased out in Israel under the Montreal Protocol. In laboratory studies, the influence of 40°, 45°, 50° and 55°C on the
levels of disinfestation and mortality ofCarpophilus hemipterus larvae was examined over a 2-h exposure period. The ratio of the number of insects found outside the feeding sites to the
total number of insects, was greatest at 50°C (92.3%), significantly greater than at 40° and 55°C. At 50° and 55°C, 100% mortality
was obtained. Since drying temperatures for most date varieties is between 45° and 50°C, and because percent disinfestation
and control was most effective at 50°C, these findings were examined under field conditions. Field trials were carried out
at a commercial drying station where the crated dates are placed on the ground inside a plastic-clad hothouse. The stacks
were covered with plastic liners to form ‘drying ducts’ through which heated air was sucked using fans positioned at the opposite
end of the ducts. It was shown that from 1 to 2 h were required for the dates to reach the set temperature of 50°C. During
the following 2-h aeration, the dates were exposed to 50°C heated air, after which an examination of infested dates inserted
into the drying ducts, and natural infestations showed that successful control and emigration were obtained. This method produced
results comparable to those obtained with methyl bromide fumigation, and was suitable as a replacement technology for infestation
control.
http://www.phytoparasitica.org posting Nov. 7, 2005. 相似文献
138.
One of the major acarine pest species of deciduous fruit trees like apple and plum is the European red mite, Panonychus ulmi KOCH (Acari: Tetranychidae). Feeding damage by P. ulmi results in leaf bronzing followed by an early defoliation and a reduction in yield, which is usually prevented by the application of acaricides. A problem often associated with mite control is the (sometimes rapid) development of resistance due to their high reproductive potential, a short life cycle allowing numerous generations per season and frequent applications of acaricides. Therefore a resistance monitoring is considered to be an essential part within resistance management strategies where only compounds providing full efficacy at recommended rates should be used. Once a new acaricide is considered for market introduction a so-called baseline susceptibility study is requested by the European authorities. Such a baseline study was also conducted for the new acaricidal compound spirodiclofen (Envidor®), which is known to inhibit lipid biosynthesis and particularly active against juvenile stages of tetranychid mite pests such as P. ulmi. However, a strong reduction of female adult fecundity results in excellent residual efficacy. Here we report on the baseline susceptibility of 15 European red mite populations against spirodiclofen, which were collected in 2005 in apple orchards at Lake Constance, Germany. The baseline data were combined because of a low population-to-population variation in response to spirodiclofen and a composite dose effect calculation revealed a diagnostic concentration (LC95) of 5?mg/liter (ppm) for future monitoring purposes in P. ulmi larvae. Furthermore we checked the susceptibility of the very same field populations against pyridaben, hexythiazox and abamectin. This helps to identify candidates for a balanced resistance management strategy avoiding the implication of cross-resistance issues. 相似文献
139.
The sexual season, i.e. the sexual cycle activity, of Finn × German Mutton Merino (Finn × GMM) ewes was found to extend from August to March. In a group of purebred German Mutton Merino (GMM) ewes the sexual season extended from June to January.After July–August and October–November lambings, 90–95% of the Finn × GMM crosses renewed postpartum sexual activity within 90 and 75 days, respectively. Only 40% of the November lambing purebred GMM ewes started new cycles within 105 days postpartum.The responsiveness of the Finn × GMM ewes to hormonal treatment was high (90–100%) during different months of the year. The fertility at the synchronized or induced oestrus was 60–75% throughout the year, with a mean litter size of 2.0 lambs per lambing. 相似文献
140.