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121.
Toon?De PessemierEmail author Sam?Coppens Kristof?Geebelen Chris?Vleugels Stijn?Bannier Erik?Mannens Kris?Vanhecke Luc?Martens 《Multimedia Tools and Applications》2012,58(1):167-213
Nowadays, most people have limited leisure time and the offer of (cultural) activities to spend this time is enormous. Consequently,
picking the most appropriate events becomes increasingly difficult for end-users. This complexity of choice reinforces the
necessity of filtering systems that assist users in finding and selecting relevant events. Whereas traditional filtering tools
enable e.g. the use of keyword-based or filtered searches, innovative recommender systems draw on user ratings, preferences,
and metadata describing the events. Existing collaborative recommendation techniques, developed for suggesting web-shop products
or audio-visual content, have difficulties with sparse rating data and can not cope at all with event-specific restrictions
like availability, time, and location. Moreover, aggregating, enriching, and distributing these events are additional requisites
for an optimal communication channel. In this paper, we propose a highly-scalable event recommendation platform which considers
event-specific characteristics. Personal suggestions are generated by an advanced collaborative filtering algorithm, which
is more robust on sparse data by extending user profiles with presumable future consumptions. The events, which are described
using an RDF/OWL representation of the EventsML-G2 standard, are categorized and enriched via smart indexing and open linked
data sets. This metadata model enables additional content-based filters, which consider event-specific characteristics, on
the recommendation list. The integration of these different functionalities is realized by a scalable and extendable bus architecture.
Finally, focus group conversations were organized with external experts, cultural mediators, and potential end-users to evaluate
the event distribution platform and investigate the possible added value of recommendations for cultural participation. 相似文献
122.
Anabela S. Ramalho Mieke Boon Marijke Proesmans Franois Vermeulen Marianne S. Carlon Kris De Boeck 《International journal of molecular sciences》2022,23(3)
Cystic fibrosis, a multi-organ genetic disease, is characterized by abnormal function of the cystic fibrosis transmembrane conductance regulator (CFTR) protein, a chloride channel at the apical membrane of several epithelia. In recent years, therapeutic strategies have been developed to correct the CFTR defect. To evaluate CFTR function at baseline for diagnosis, or the efficacy of CFTR-restoring therapy, reliable tests are needed to measure CFTR function, in vitro, ex vivo and in vivo. In vitro techniques either directly or indirectly measure ion fluxes; direct measurement of ion fluxes and quenching of fluorescence in cell-based assays, change in transmembrane voltage or current in patch clamp or Ussing chamber, swelling of CFTR-containing organoids by secondary water influx upon CFTR activation. Several cell or tissue types can be used. Ex vivo and in vivo assays similarly evaluate current (intestinal current measurement) and membrane potential differences (nasal potential difference), on tissues from individual patients. In the sweat test, the most frequently used in vivo evaluation of CFTR function, chloride concentration or stimulated sweat rate can be directly measured. Here, we will describe the currently available bio-assays for quantitative evaluation of CFTR function, their indications, advantages and disadvantages, and correlation with clinical outcome measures. 相似文献
123.
Desorption or evaporation is one of the mechanisms for loss of perfluoropolyalkylether (PFPE) lubricants from the surfaces of data storage media. One approach to minimizing PFPE loss to desorption is the use of lubricants with increasing molecular weight or increasing average chain length. In order to understand the effects of chain length on the lubricant evaporation kinetics we have studied the desorption kinetics of monolayer films of oligomeric ethers with varying chain length adsorbed on the surface of graphite. The desorption pre-exponents, v, and desorption barriers, E
des
, have been measured for poly(ethylene glycol) dimethyl ethers, CH3O(CH2CH2O)
m
CH3, with m=1,2,3,4,8 and 10. These are models for the PFPE known as Fomblin Z, which has a structure CF3O(CF2CF2O)
x
(CF2O)
y
CF3. The results show that the desorption pre-exponents are independent of chain length and have an average value of v=1018.7±0.3 s–1. The E
des
for the poly(ethylene glycol) dimethyl ethers vary non-linearly with chain length and can be fit with a power law expression of the form E
des
=a+bN
, where N is the total number of atoms in the oligomer backbone (N=3m+3) and the scaling exponent has a value of 1/2. This non-linear dependence of E
des
on chain length has also been observed in recent studies of the desorption kinetics of straight chain alkanes from graphite. A desorption mechanism is described that explains the non-linearity of E
des
for the poly(ethylene glycol) dimethyl ethers. The implication for the lifetime of lubricants on data storage media is that the long chain PFPE lubricants desorb more rapidly than one might expect based on simple linear scaling of the E
des
of lower molecular weight PFPEs. 相似文献
124.
Maleena Imbeah Kris Angkanaporn Velmurugu Ravindran Wayne L. Bryden 《Journal of the science of food and agriculture》1996,72(2):213-218
The present study was conducted to compare the efficacy of five different reaction conditions on the guanidination of lysine in casein and to establish optimum lysine: O -methylisourea (OMIU) for maximum guanidination of lysine in casein and soya bean meal. The results indicate that the presence of glycine–NaOH buffer is not required for guanidination of proteins at pH 10·5. A OMIU concentration of 0·4 M was found to be as effective as 0·6 M for guanidination. Both OMIU–hydrogen sulphate and free OMIU were equally effective reagents in terms of conversion of lysine to homoarginine. The use of OMIU–hydrogen sulphate for guanidination and the use of ethanol to recover guanidinated protein, however, resulted in the formation of crystalline sodium sulphate, a known purgative agent, in the guanidinated material, and therefore are not recommended if the guanidinated protein is to be used in animal trials. The molar ratio of lysine: OMIU required for efficient lysine conversion to homoarginine varied for different protein sources. Ratios required for maximum conversion for casein and soya bean meal were determined to be 1:10 and 1:16, respectively. A simple procedure developed for the large-scale guanidination (5–10 kg batches) of proteins is also described. The results showed that guanidination of proteins can be easily scaled up from 20 g to 5–10 kg and that large-scale guanidination is feasible and efficient. 相似文献
125.
Kris Villez Gürkan Sin Peter A Vanrolleghem Magda Ruiz Joan Colomer Christian Rosén Peter A Vanrolleghem 《Water science and technology》2008,57(10):1659-1666
A methodology based on Principal Component Analysis (PCA) and clustering is evaluated for process monitoring and process analysis of a pilot-scale SBR removing nitrogen and phosphorus. The first step of this method is to build a multi-way PCA (MPCA) model using the historical process data. In the second step, the principal scores and the Q-statistics resulting from the MPCA model are fed to the LAMDA clustering algorithm. This procedure is iterated twice. The first iteration provides an efficient and effective discrimination between normal and abnormal operational conditions. The second iteration of the procedure allowed a clear-cut discrimination of applied operational changes in the SBR history. Important to add is that this procedure helped identifying some changes in the process behaviour, which would not have been possible, had we only relied on visually inspecting this online data set of the SBR (which is traditionally the case in practice). Hence the PCA based clustering methodology is a promising tool to efficiently interpret and analyse the SBR process behaviour using large historical online data sets. 相似文献
126.
Frederik Hammes Arsne Seka Kris Van Hege Tom Van de Wiele Jan Vanderdeelen Steven D Siciliano Willy Verstraete 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2003,78(6):670-677
High concentrations of soluble calcium in industrial wastewater present problems due to the calcification of downstream processing. The current trend towards circuit closure and increased water re‐use will escalate this problem. We investigated ureolytic microbial carbonate precipitation as a novel process for removing excess calcium from industrial effluents. Two laboratory‐scale reactors, both with a hydraulic retention time of 8 h, were fed with 1.8 dm3 of anaerobic effluent (about 11 mM Ca2+) from a paper recycling plant. Both reactors were inoculated with pre‐cultivated calcareous sludge and the treatment reactor was additionally dosed with urea to a final concentration of 8.3 mM . Even though the anaerobic wastewater was saturated as such with respect to CaCO3, urea addition and hydrolysis was shown to be a pre‐requisite for precipitation. Almost all (85–90% w/v) of the soluble calcium was precipitated as CaCO3 and removed through sedimentation in the treatment reactor. This bio‐catalytic process presents an uncomplicated and efficient method for the removal of calcium from industrial wastewater. Copyright © 2003 Society of Chemical Industry 相似文献
127.
无线传感器是一种非常微小、精密的,内嵌微处理器的设备,其特点在于当传感器在区域内布点后,这些节点不能再充电;所以在无线传感器网络设计中,能量的开销及网络负载平衡是首先应考虑的因素.提出了一种能量自调式Q路由算法(Q routing with energy and position awareness).使用开放的模拟器OMNET ,比较了QREA协议与传统的路由协议一完全位置路由(geographical routing)的性能.通过实验得出了一个近优化的路由模型. 相似文献
128.
Christen K 《Environmental science & technology》2005,39(5):101A-102A
129.
Christen K 《Environmental science & technology》2005,39(15):312A-313A
130.