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This study developed an artificial neural network (ANN) to estimate the growth of microorganisms during a fermentation process.
The ANN relies solely on the cumulative consumption of alkali and the buffer capacity, which were measured on-line from the
on/off control signal and pH values through automatic pH control. The two input variables were monitored on-line from a series
of different batch cultivations and used to train the ANN to estimate biomass. The ANN was refined by optimizing the network
structure and by adopting various algorithms for its training. The software estimator successfully generated growth profiles
that showed good agreement with the measured biomass of separate batch cultures carried out between at 25 and 35_C. 相似文献
664.
Background, aim, and scope Life cycle assessment (LCA) has been considered one of the tools for supporting decision-making related to the environmental
aspects of a product system. It has mainly been used to evaluate the potential impacts associated with relevant inputs and
outputs to/from a given product system throughout its life cycle. In most cases, LCA has not considered the impacts on the
internal environment, i.e. working environment, but only the external environment. Recently, it has been recognized that the
consideration of the impacts on the working environment as well as on the external environment, is needed in order to assess
all aspects of the effects on human well-being. To this end, this study has developed a total environmental assessment methodology
which enables one to integrate both the working environment and the external environment into the conventional LCA framework.
Materials and methods In general, the characteristics of the impacts on the external environment are different from those on the working environment.
In order to properly integrate the two types into total environmental impacts, it is necessary to define identical system
boundaries and select impact category indicators at the same level. In order to define the identical system boundary and reduce
the uncertainties of LCI results, the hybrid IOA (input–output analysis) method, which integrates the advantages between conventional
LCI method and IOA method, is introduced to collect input and output data throughout the entire life cycle of a given product.
For the impact category indicators at the endpoint level, LWD (Lost Work Days) is employed to evaluate the damage to human
health and safety in the working environment, while DALY (disability-adjusted life years) and PAF (Potentially Affected Fraction)
are selected to evaluate the damage to human health and eco-system quality in the external environment, respectively.
Results and discussion The environmental intervention factors (EIFs) are developed not only for the data categories of resource use, air emissions,
and water emissions, but also for occupational health and safety to complete a life cycle inventory table. For the development
of the EIFs on occupational health and safety, in particular, the number of workers affected by i hazardous items and the number of workers affected at the i magnitude of disability are collected. For the characterization of the impact categories in the working environment, such
as occupational health and safety, the exposure factors, effect factors, and damage factors are developed to calculate the
LWD of each category. For normalization, the normalization reference is defined as the total LWD divided by the total number
of workers. A case study is presented to illustrate the applicability of the proposed method for the integration of the working
environment into the conventional LCA framework.
Conclusions This study is intended to develop a methodology which enables one to integrate the working environmental module into the conventional
LCA framework. The hybrid IOA method is utilized to extend the system boundary of both the working environment module and
the external environment module to the entire life cycle of a product system. In this study, characterization models and category
indicators for occupational health and safety are proposed, respectively, while the methodology of Eco-indicator 99 is used
for the external environment. In addition to aid further understanding on the results of this method, this study introduced
and developed the category indicators such as DALY, and LWD, which can be expressed as a function of time, and introduced
PAF, which can be expressed as a probability.
Recommendations and perspectives The consideration of the impacts not only on the external environment, but also on the working environment, is very important,
because the best solution for the external environment may not necessarily be the best solution for the working environment.
It is expected that the integration of occupational health and safety matters into the conventional LCA framework can bring
many benefits to individuals, as well as industrial companies, by avoiding duplicated measures and false optimization. 相似文献
665.
Edwina Wing-Lun Sally A. Eaton Suzy S. J. Hur Alastair Aiken Paul E. Young Michael E. Buckland 《Epigenetics》2016,11(7):475-481
The complex interaction between obesity, Western-style diets, and cardiovascular disease is of increasing interest, with a growing number of children being born to obese parents with poor lifestyle choices. These offspring have themselves an increased susceptibility to obesity and subsequent cardiovascular disease in adult life, which may be ‘programmed’ by their intrauterine environment. Cardiac microRNAs (miRNAs) are affected by multiple disease states, and have also been shown to be capable of exerting a hormone-like control on whole body metabolism. Here we sought to determine the effect of prenatal exposure to maternal obesity and/or postnatal exposure to a Western diet on miRNA expression in the heart. Unbiased small RNA sequencing was carried out on cardiac tissue from young adult mice born to lean or obese mothers; offspring were weaned onto either a low-fat control diet or a high-fat Western-style diet. We found 8 cardiac miRNAs that were significantly altered in response to maternal obesity, but only when the offspring were challenged postnatally with the Western diet. In contrast, postnatal exposure to the diet alone induced significant changes to the expression of a much larger number of miRNAs (33 in offspring of lean and 46 in offspring of obese). Many of the affected miRNAs have previously been implicated in various cardiac pathologies. The pervasive cardiac miRNA changes induced by a Western diet suggest that an individual's lifestyle choices outweigh the impact of any programming effects by maternal obesity on miRNA-related cardiac health. 相似文献
666.
Hyun Sung Kim Sang Joon Kim Hui Jung Kim Han Uk Kim Sang Joem Ahn Byung-Ki Hur 《Biotechnology and Bioprocess Engineering》2006,11(3):215-222
The Lowry method was used in this study to measure protein inHaemophilus influenzae type b (Hib) conjugate vaccines (polyribosylibitol phosphate-tetanus toxoid; PRP-TT) using deoxycholic acid (DOC) to induce
protein precipitation. Trichloroacetic acid (TCA) did not induce precipitation adequately from the Hib conjugate bulk and
the freeze-dried Hib conjugate product. Its yield was approximately 50%. The matrix structure of Hib conjugate inhibits precipitation
by TCA. Although the Lowry method can be carried out without precipitation in Hib conjugate bulk when no residual impurities
(adipic acid dihydrazide [ADH], 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide-HCI [EDAC], phenol and cyanogens bromide [CNBr],etc.) are present, it cannot be used for Hib conjugate products that contain sucrose 8.5%, because 8.5% concentration of sucrose
enhanced the protein concentration. DOC- and HCI-induced precipitation is an alternative method for evaluating the protein
content of the Hib conjugate bulk and the Hib conjugate product. The precipitation was optimal with a final concentrate of
0.1% for DOC at 4°C and pH 2. This Lowry method, using DOC/HCI precipitation to induce protein precipitation, was confirmed
a consistent, reproducible, and valid test for proteins in Hib conjugate bulk and its freeze-dried product. 相似文献