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1.

Objectives

To describe colostrum management practices carried out in northern Victorian dairy herds and to identify weaknesses in these areas that may affect calf health and welfare by comparing the results with the current industry recommendations

Methods

A questionnaire to obtain information about colostrum management and calf‐rearing practices was sent to commercial dairy farming clients of Rochester Veterinary Practice between June and September 2013. The questionnaire consisted of a general herd overview and colostrum harvesting practices.

Results

The response rate was 39% (58/150). Many dairy producers were not meeting the current industry recommendations in the following areas: (1) time of removal calf from the dam, (2) relying on calf suckling colostrum from the dam to achieve adequate passive transfer, (3) failing to supplement calves with colostrum, (4) feeding inadequate volumes of colostrum, (5) delayed colostrum harvesting, (6) pooling of colostrum, (7) failing to objectively assess colostrum quality or relying on visual assessment and (8) storing colostrum for a prolonged periods of time at ambient temperatures.

Conclusion

The results from this survey highlight the need for greater awareness of industry standards for colostrum management and feeding hygiene.
  相似文献   
2.
Four homoisoflavonoids, 4-O-methylsappanol (1), protosappanin A (2), brazilin (3) and caeasalpin J (4), isolated from Caesalpinia sappan, were tested for inhibitory activity against Beauveria bassiana. Compound 1 showed activity against this fungus.  相似文献   
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A mathematical model for simulating soil water content in the root zone was developed by taking into consideration soil physical properties, crop and climatic parameters. The governing differential equation for unsaturated flow of water in the soil was solved numerically using the Crank-Nicholson finite difference technique. The water uptake by plants was simulated by using two different sink functions. The model predictions were in good agreement with field data and thus it is possible to schedule irrigations.  相似文献   
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N. N. Roy  B. R. Murty 《Euphytica》1970,19(4):509-521
Summary A simple and effective selection procedure for identifying lines with wide adaptation and ability to do well under drought is outlined, supported with experimental data involving diverse and high yielding populations of bread wheat.The effect of selections for local adaptation to stress environment is found to be inferior as compared to selection for developmental traits in a favourable environment. Data on selection for developmental traits have shown favourable correlated associations with more precision in the estimate of components of genetic variation and heritability and larger magnitude of response to selection as compared to selection for yield components in stress environment.The developmental characters such as early vigour and synchronous tillering, days to heading and ear length which show stability over different environments are found to be important components of wide adaptation and productivity under moisture-stress.Presented at the Symposium on Planning for the Drought of the National Institute of Sciences, held in New Delhi, India, 4–6 May, 1969.  相似文献   
7.
Summary Two crosses of sorghum, Sorghum bicolor (L.) Moench (IS 1054 × ICSV-1, and IS 5604 × IS 1054) were evaluated in parental, F1, F2, and backcross generations for the variation in their popping quality as measured by pop volume (ml). Dominance was in the direction of low pop volume. Dominance and additive gene effects, in that order, governed most of the variation, while significant dominance x dominance type of interaction effects could also be detected. There was no evidence for higher order gene interactions.Approved as Journal Article 630 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, P.O. 502 324, Andhra Pradesh, India.  相似文献   
8.
The output from the modified version of a hydrodynamical numerical model developped earlier by El-Sabh and Murty (1988) has been used to hindcast the movement and dispersion of oil slicks in the Arabian Gulf during part of the period of January to March 1991. While other studies on numerical simulations of this event pertain mainly to the Al-Ahmadi spill, the present study simultaneously examines the movement of oil from not only this source but also from Mina Al-bakr and clearly delineates the impact of oil from each of these sources. The numerical model is used for computing the currents due to tides, winds and bathymetric influences. This model has only one open boundary at the strait of Hormuz where the incoming tide is prescribed. The model time step is 100 seconds, sufficient to resolve the hydrodynamical effects. However, the slick movement simulations are carried out with current fields determined at hourly intervals. The surface wind field has been computed from synoptic weather charts using the geostropic relationship, supplemented by some climatological data. The oil slick is advected by the net current as obtained above and the lateral spreading of the oil is simulated through a random walk process with an appropriate eddy diffusion coefficient. The influence of the magnitude of the eddy diffusion coefficient on the spread of the oil is examined in detail. Refloatation of beached oil parcels is also considered in the model simulations. The model simulations are compared with slick location as obtained from remotely sensed observations. The importance of real-time winds in spill movement prediction is demonstrated through a comparison with model simulations obtained with monthly mean climatological winds.  相似文献   
9.
Angle-resolved photoemission experiments reveal evidence of an energy gap in the normal state excitation spectrum of the cuprate superconductor Bi2Sr2CaCu2O8+delta. This gap exists only in underdoped samples and closes around the doping level at which the superconducting transition temperature Tc is a maximum. The momentum dependence and magnitude of the gap closely resemble those of the dx2-y2 gap observed in the superconducting state. This observation is consistent with results from several other experimental techniques, which also indicate the presence of a gap in the normal state. Some possible theoretical explanations for this effect are reviewed.  相似文献   
10.
Observations on gaseous and particulate pollutants were undertaken at four locations in the region of a thermal power plant (TPP), which is under construction at Tuticorin, south India. The predicted concentrations Of SO2 due to the emissions from the TPP and its possible impact on the inhabitants and climate in the downwind region were evaluated. Also, the predicted concentrations downwind of a Petrochemical Industrial Complex (PIC) located in the vicinity of the TPP were computed and compared with the measured concentrations. The predicted maximum concentration of SO2 at 6 km downwind of TPP is about 530 μg m?3 under most favourable wind conditions. The anticipated increase in SO2 due to the thermal power plant under construction may therefore be substantial. The predicted concentrations Of SO2, at a distance of 1.8 km downwind of the PIC, varied between 34 and 216 μg m?3 for wind directions ranging from 70 to 90° and for Pasquill stability category C. The plume would be over the observational site when the wind direction is 80°. The maximum measured concentration was 23 ug m?3. The discrepancy was due to the rapid fluctuations in the wind direction during the observational period over a wide range from 20 to 90°.  相似文献   
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