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31.
D.K. Lovett E.R. Deaville D.I. Givens M. Finlay E. Owen 《Animal Feed Science and Technology》2005,120(3-4):323-332
Maize silage nutritive quality is routinely determined by near infrared reflectance spectroscopy (NIRS). However, little is known about the impact of sample preparation on the accuracy of the calibration to predict biological traits. A sample population of 48 maize silages representing a wide range of physiological maturities was used in a study to determine the impact of different sample preparation procedures (i.e., drying regimes; the presence or absence of residual moisture; the degree of particle comminution) on resultant NIR prediction statistics. All silages were scanned using a total of 12 combinations of sample pre-treatments. Each sample preparation combination was subjected to three multivariate regression techniques to give a total of 36 predictions per biological trait. Increased sample preparations procedure, relative to scanning the unprocessed whole plant (WP) material, always resulted in a numerical minimisation of model statistics. However, the ability of each of the treatments to significantly minimise the model statistics differed. Particle comminution was the most important factor, oven-drying regime was intermediate, and residual moisture presence was the least important. Models to predict various biological parameters of maize silage will be improved if material is subjected to a high degree of particle comminution (i.e., having been passed through a 1 mm screen) and developed on plant material previously dried at 60 °C. The extra effort in terms of time and cost required to remove sample residual moisture cannot be justified. 相似文献
32.
This article focuses on the transformation of the female reproductive body with the use of assisted reproduction technologies
under neo-liberal economic globalisation, wherein the ideology of trade without borders is central, as well as under liberal
feminist ideals, wherein the right to self-determination is central. Two aspects of the body in western medicine—the fragmented
body and the commodified body, and the integral relation between these two—are highlighted. This is done in order to analyse
the implications of local and global transactions in women’s reproductive body parts for their right to self-determination
and individual agency and what this means for their embodiment. We conclude by exploring whether women can become embodied
subjects by exercising their proprietary right to their bodies through directing technology to achieve their own goals, while
at the same time being fragmented into parts and losing their personhood and bodily integrity.
This article has been translated and adapted from the Dutch version published in the Tijdschrift voor Humanistiek, 2006; 26(7). 相似文献
33.
Rob Vreeker Liangbin Li Yapeng Fang Ingrid Appelqvist Eduardo Mendes 《Food biophysics》2008,3(4):361-369
In this paper, we study the rehydration properties of air-dried calcium alginate gel beads. Rehydration is shown to depend
on alginate source (i.e. mannuronic to guluronic acid ratio) and the salt concentration in the rehydration medium. Rehydration
curves are described adequately by the empirical Weibull equation. Wide-angle X-ray diffraction measurements are performed
to obtain information on the microstructure of dried alginate gels. The X-ray diffraction patterns provide evidence for formation
of ordered domains in which alginate polymers are laterally associated. Formation of ordered structures during drying is found
to have a large impact on rehydration properties. Lateral association of alginate chains is reduced (and rehydration improved)
by removing excess calcium ions from the gel beads in a washing step prior to air drying. In addition, rehydration properties
of mixed alginate–carboxymethyl cellulose (CMC) gel beads are investigated. The presence of CMC in the gel matrix is found
to reduce lateral association of alginate chains during drying and to improve rehydration properties. 相似文献
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35.
A pilot scale fluidized bed dryer with inert particles as energy carrier was used to investigate the drying characteristics of carrot in this type of dryer. Glass beads, hollow steel balls and pieces of dry carrot were used as inert materials. The effects of sample diameter, inert material type, inert material diameter, amount of inert material, air velocity and temperature on the rate of drying were studied. It was found that the presence of inert particles enhances the rate of drying. The results of this study also revealed that, although the rate of drying increased with decreasing sample diameter, increasing of inert material thermal conductivity, and increasing of air temperature, but the inert material diameter and air velocity did not have any significant effect on the rate of drying. The independence of the rate of drying on air velocity in well fluidized systems, indicates that external diffusion is not the controlling step in this process. It was also found that the presence of inert materials caused the drying material to reach its final internal temperature more rapidly. The internal temperature of the drying material, also increased with increasing diameter and thermal conductivity of the inert materials. 相似文献
36.
To assess the potential of short-term screenings for drought resistance at the seedling stage to detect ecotypic variation
and predict field performance, we studied the responses to water deficit of seedlings of Pinus canariensis from five geographic origins under controlled conditions and compared these responses with the performance of provenances
in a multi-site field trial. Leaf water potential, the osmotic component, leaf chlorophyll fluorescence and growth and biomass
partitioning were measured as seedlings were subjected for 11 days to two levels of osmotic potential generated by polyethylene
glycol (PEG 6000), −1 MPa (slowly imposed water deficit; S) and −1.5 MPa (fast imposed water deficit; F), and a control treatment
(no PEG added to the nutrient solution; C). Leaf water potential declined to final mean values of −1.2, −2.7 and −4.7 MPa
in the C, S and F treatments, respectively. The ratio of variable to maximum chlorophyll fluorescence declined to final mean
values of 0.77, 0.66 and 0.40 in the C, S and F treatments, respectively, with no differences amongst provenances. All provenances
showed an active osmotic adjustment (OA) in response to water deficit which varied depending on the drying rate. A slow imposition
of water deficit favoured solute accumulation. Pooling all treatments, the index of OA ranged from 0.28 to 0.40, but rose
considerably when only C and S treatments were considered (0.56 to 0.70). There was a positive and significant correlation
between the overall index of OA (all treatments pooled) and the drought period in the site of origin, suggesting ecotypic
variation in OA as a result of drought duration. Seedlings allocated more dry matter to roots than shoots when subjected to
moderate and slowly imposed water deficit; only one provenance showed no increase in the root to shoot ratio at the end of
the treatment period compared with control seedlings. Responses to controlled water deficits were only qualitatively related
to performance (survival and growth) of provenances in several field sites, indicating the involvement of complex mechanisms
to cope with drought under natural conditions. However, the provenance with the highest overall index of OA outgrew and outsurvived
the other provenances in the most arid site, and the only provenance not modifying the root to shoot ratio in response to
water deficit survived the least in all field sites. Acclimation of root to shoot ratio and net solute accumulation to water
deficit could hence favour drought-tolerance beyond the seedling stage and be used as preliminary predictors of field performance. 相似文献
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39.
本文对2022年《生物工程学报》发表的与合成生物制造相关的综述和研究论文进行了评述,重点讨论了DNA测序、DNA合成、DNA编辑、基因表达调控和数学细胞模型等底层技术,酶的设计、改造和应用技术,化学品生物催化、氨基酸及其衍生物、有机酸、天然化合物、抗生素与活性肽、功能多糖、功能蛋白质等重要产品的生物制造技术,一碳化合物和生物质原料利用技术以及合成微生物组技术,以帮助读者从一个侧面了解合成生物制造相关技术和产业的发展情况。 相似文献