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41.
Buffalo heifers selected for lower residual feed intake have lower feed intake,better dietary nitrogen utilisation and reduced enteric methane production
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V. K. Sharma S. S. Kundu C. Datt S. Prusty M. Kumar U. B. Sontakke 《Journal of animal physiology and animal nutrition》2018,102(2):e607-e614
This study was conducted to evaluate the utilisation of the residual feed intake (RFI ) as a feed efficiency selection tool and its relationship with methane emissions. Eighteen Murrah buffalo (Bubalus bubalis ) heifers were fed ad libitum with total mixed ration (TMR ) for 120 days. Based on linear regression models involving dry matter intake (DMI ), average daily gain (ADG ) and mid‐test metabolic body size (MBW 0.75), heifers were assigned into low and high RFI groups. The RFI varied from ?0.09 to +0.12 kg DM /day with average RFI of ?0.05 and 0.05 kg DM /day in low and high RFI heifers respectively. Low RFI heifers ate 11.6% less DM each day, yet average daily gain (ADG ) and feed utilisation were comparable among low and high RFI groups. Low RFI heifers required significantly (p < .05) less metabolizable energy for maintenance (ME m) compared to high RFI heifers. Apparent nutrient digestibility showed non‐significant difference (p > .05) among low and high RFI groups. Although the nitrogen balance was similar among heifers of low and high RFI groups, nitrogen metabolism was significantly higher (p > .05) in high RFI heifers. Comparison of data from heifers exhibiting the low (n = 9) and high (n = 9) RFI showed that the low RFI heifers have lower enteric methane production and methane losses than high RFI heifers. In conclusion, results of this study revealed that selection of more efficient buffalo heifers has multiple benefits, such as decreased feed intake and less emission of methane. 相似文献
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M. Kundu 《Agricultural Water Management》2008,95(4):383-390
The hypothesis was tested, whether soil wetness and phosphorus status could regulate the evapotranspiration rate (ETR), which is of special interest in the lower Gangetic Plain. Rajmash was grown during November-February of 2003-2004 and 2004-2005 on a sandy loam soil, and was irrigated when cumulative pan evaporation (CPE) attained the value of 33 mm (CPE33); 44 mm (CPE44) and 66 mm (CPE66). Four levels of phosphate application were 0 kg P2O5 ha−1 (P0); 30 kg P2O5 ha−1 (P30); 60 kg P2O5 ha−1 (P60) and 90 kg P2O5 ha−1 (P90). Seed yield under CPE33 was 1.37 Mg ha−1 and reduced by 18% and 35%, respectively under CPE44 and CPE66. Continuous increasing trend in yield was recorded with an increase in phosphate level (PL). Irrespective of growth stages, similar trends were recorded for leaf area index (LAI). Maximum variation in LAI among the treatments was recorded at 60 days after sowing. On average, actual ETR was 1.37 mm day−1 under CPE33 and declined by 13% and 16% under CPE44 and CPE66, respectively. Variation in ETR under different PL was highest under CPE33 and lowest under CPE44. Except P90, irrespective of PL, highest value of water use efficiency (WUE) was obtained under CPE44. However, magnitude of net evapotranspiration efficiency (WUEET) and irrigation efficiency (WUEI) attained the highest level under CPE33 regime. All water use indices showed an increasing trend with the increase in phosphate level from 0 to 90 kg ha−1. Impact of phosphorus on various parameters was pronounced under CPE33. 相似文献
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Kulbhushan Samal Kuntal Maiti Kaustubha Mohanty Chandan Das 《Water, air, and soil pollution》2018,229(3):96
The performance of spinning basket membrane (SBM) module was tested for the separation of polyvinyl alcohol (PVA) from wastewater. The SBM performance was examined using 50 kDa polyethersulfone ultrafiltration membrane under different parametric conditions. Also, the effects of rotational speed and transmembrane pressure on permeate flux and PVA rejection were investigated. The rotational speed played a significant role in decreasing membrane fouling by reducing the particle deposition on the membrane surface due to enhanced turbulence and shear force. Also, the in-built hydrodynamic cleaning facility of the SBM module allowed easy cleaning of the membrane. The steady-state value of percentage rejection of PVA was above 90% when the steady-state permeate flux value was above 54% of its initial value. The results suggested that spinning basket membrane module was efficient as well as economical for the separation of PVA from aqueous solution. 相似文献
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A protocol of multiplex RT-PCR in a one-tube system for the detection of the most common stone fruit trees viruses [e.g., plum pox virus (PPV), prune dwarf virus (PDV), and Prunus necrotic ringspot virus (PNRSV)], including the internal control of NADH dehydrogenase subunit 5 (nad5) gene are described here. The method specificity was tested on more than 80 different samples with various isolates and strains of the viruses. It showed that the targeted viruses produced the expected amplicons, whereas all other related viruses produced only the nad5 internal control amplicon. The method sensitivity was evaluated by comparing it with Simplex RT-PCR with the same primers; no significant differences in detection limits were recorded. Furthermore, the competitiveness of the primers in the assay was tested by serial RNA dilutions of samples with mixed and single infections. The least competitive was the internal control nad5 gene primer pair; therefore, there is a reduced risk of false negatives as all the other primers tend to be more efficient in the given primer cocktail than in the primers for internal control. 相似文献
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Renu Yadav Meenal Joshi Snehal Wanjari Chandan Prabhu Swati Kotwal T. Satyanarayanan Sadhana Rayalu 《Water, air, and soil pollution》2012,223(8):5345-5356
Carbonic anhydrase (CA) has been immobilized on chitosan stabilized iron nanoparticles (CSIN) for the biomimetic carbonation reaction. CSIN was characterized using scanning electron microscope, energy dispersive X-ray, X-ray diffraction spectroscopy, and Fourier transform infrared analysis. The effect of various parameters such as pH, temperature and storage stability, on immobilized CA was investigated using a p-NPA assay. Kinetic parameters of immobilized and free CA (K m and V max values) were also evaluated. The K m and V max for immobilized CA was 1.727?mM and 1.189???mol?min?1?ml?1, respectively, whereas for free enzyme the K m and V max was 1.594?mM and 1.307???mol?min?1?ml?1, respectively. It was observed that the immobilized enzyme had longer storage stability and retained 50?% of its initial activity upto 30?days at room temperature. CA immobilized on CSIN has been used for hydration of CO2, and the results were validated by using a gas chromatographic method. Proof of concept has been established for the biomimetic carbonation reaction. Immobilized CA show reasonably good CO2 sequestration capacity of 21.55?mg of CaCO3/mg of CA as compared to CO2 sequestration capacity of 34.92?mg of CaCO3/mg of CA for free CA respectively, under a limiting concentration of CO2 (14.5?mg of CO2/10?ml). 相似文献
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Prosanta Saha Debabrata Sarkar Avijit Kundu Subhabrata Majumder Swapan K. Datta Karabi Datta 《Genetic Resources and Crop Evolution》2014,61(6):1173-1188
Here, we report the karyotypes and mean haploid idiograms of the ten Asian Corchorus species (2n = 2x = 14). Chromosomes were small, with a mean chromosome length of 2.30 μm. The largest chromosome was recorded in C. pseudo-olitorius (3.50 μm) and the shortest in C. pseudocapsularis (1.60 μm). The karyotypes of the two cultivated species (C. capsularis and C. olitorius) and C. pseudo-olitorius were the most diverse and specialized, whereas those of C. depressus and C. trilocularis were the least diverse. C. fascicularis had the most asymmetrical and C. urticifolius the most symmetrical karyotypes. An increase in genome size was accompanied by increasing karyotype diversity in terms of morphologically distinct chromosome types and interchromosomal asymmetry, with uneven distribution of additional DNA throughout the karyotype. A positive correlation between interchromosomal asymmetry and dispersion index suggested that size differences between chromosomes were mainly associated with karyotype asymmetry. Karyotypes of the Corchorus species became progressively asymmetrical in the course of evolution. Relationships among the ten Corchorus species were defined by using a neighbor-joining tree inferred from inter-simple sequence repeat data. C. fascicularis and C. pseudocapsularis, with shorter karyotypes and smaller genomes, were closely related to C. pseudo-olitorius and C. capsularis, respectively, which were characterized by relatively longer karyotypes and larger genomes. However, the two cultivated species with different levels of interchromosomal asymmetries, dispersion indices and genome sizes were distantly related. Taking this molecular evidence into consideration, we have discussed chromosomal evolution in relation to karyological data including genome size. 相似文献
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CH. Srinivasarao B. Venkateswarlu R. Lal A. K. Singh S. Kundu K. P. R. Vittal J. J. Patel M. M. Patel 《Land Degradation \u0026amp; Development》2014,25(2):173-183
Soil organic carbon (SOC) pools are important for maintaining soil productivity and reducing the net CO2 loading of the atmosphere. An 18‐year old long‐term field experiment involving pearl millet‐cluster bean‐castor sequence was conducted on an Entisol in western India to examine the effects of chemical fertilizers and manuring on carbon pools in relation to crop productivity and C sequestration. The data showed that even the addition of 33.5 Mg ha−1 C inputs through crop residues as well as farm yard manure could not compensate the SOC depletion by oxidation and resulted in the net loss of 4.4 Mg C ha−1 in 18 years. The loss of SOC stock in the control was 12 Mg C ha−1. Conjunctive use of chemical fertilizers along with farm yard manure produced higher agronomic yields and reduced the rate of SOC depletion. The higher average seed yields of pearl millet (809 kg ha−1), cluster bean (576), and castor (827) over six cropping seasons were obtained through integrated use of fertilizers and manure. For every Mg increase in profile SOC stock, there was an overall increase of 0.46 Mg of crop yield, comprising increase in individual yield of pearl millet (0.17 Mg ha−1 y−1 Mg−1 SOC), cluster bean (0.14) and castor (0.15). The magnitude of SOC build up was proportional to the C inputs. Carbon pools were significantly correlated with SOC, which increased with application of organic amendments. Threshold C input of 3.3 Mg C ha−1 y−1 was needed to maintain the SOC stock even at the low antecedent level. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献