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211.
Isarain-Chávez E Cabot PL Centellas F Rodríguez RM Arias C Garrido JA Brillas E 《Journal of hazardous materials》2011,185(2-3):1228-1235
The beta-blocker propranolol hydrochloride has been degraded by electrochemical advanced oxidation processes like electro-Fenton (EF) and photoelectro-Fenton (PEF) using a single cell with a Pt anode and an air diffusion cathode (ADE) for H(2)O(2) electrogeneration and a combined system containing the above Pt/ADE pair coupled in parallel to a Pt/carbon-felt (CF) cell. Organics are mainly oxidized with hydroxyl radical (OH) formed from Fenton's reaction between added Fe(2+) and electrogenerated H(2)O(2). The PEF treatment in Pt/ADE-Pt/CF system yields almost total mineralization because OH production is enhanced by Fe(2+) regeneration from Fe(3+) reduction at the CF cathode and Fe(III) complexes with generated carboxylic acids are rapidly photodecarboxylated under UVA irradiation. Lower mineralization degree is found for PEF in Pt/ADE cell due to the little influence of UVA light on Fe(2+) regeneration. The homologous EF processes are much less potent as a result of the persistence of Fe(III)-carboxylate complexes. Aromatic intermediates such as 1-naphthol, 1,4-naphthoquinone and phthalic acid and generated carboxylic acids such as pyruvic, glycolic, malonic, maleic, oxamic, oxalic and formic are identified. While chloride ion remains stable, NH(4)(+) and NO(3)(-) ions are released to the medium. A reaction sequence for propranolol hydrochloride mineralization is proposed. 相似文献
212.
Guillermo de León Pere Grima Xavier Tort‐Martorell 《Quality and Reliability Engineering International》2011,27(4):489-497
When the results of an experimental design are analyzed, in which control factors and noise factors are involved, it may be difficult to determine the combination of values of the control factors that produce the best behavior of the response, addressing both its level (or distance from the target value) and its variability. This article presents an analysis proposal that is based on the model obtained for the response and uses, as its central element, a scatter plot of its expected value vs its standard deviation. In this plot, each point corresponds to a combination of values of the control factors; thus, it is easy to identify the points with better response behavior. In our opinion, this graph provides significant advantages over the other methods that have been proposed; among them is the fact that it is always a scatter plot, regardless of the number of factors that end up being active, and that it is easy to understand and use, especially with the possibilities offered by the current statistical software packages. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
213.
Debates on the urban form have become strongly polarized between the advocates and opponents of the compact and of the dispersed or “sprawled” city. In this paper we argue that this may be the result of an excessive concentration on the study of the American experience and the neglect of other urban contexts, and examine the recent process of urban growth against the background of urban compactness and extreme densification represented by the Barcelona Metropolitan Region (BMR). The comparison of two detailed land-cover maps of 1993 and 2000 shows a progressive transformation in the traditional urban character of the region. Lower urban densities, high losses of non-urban land covers, depopulation of the metropolitan inner core, an increasing importance of single housing or the expansion of transportation infrastructures confirm the generalization of the dispersed urban model. However, the presence of numerous medium sized towns has also proved to be a deterrent of excessive dispersion. In conclusion, polycentric metropolitan areas such as the BMR may be more adjusted to absorb the negative effects of dispersion than monocentric areas. 相似文献
214.
Skrlep M Candek-Potokar M Mandelc S Javornik B Gou P Chambon C Santé-Lhoutellier V 《Meat science》2011,88(4):657-667
Two-dimensional electrophoresis was used to compare dry-cured biceps femoris insoluble protein fraction according to genotype (PRKAG3Ile199Val and CASTLys249Arg/Ser638Arg) as well as salt and pastiness level. The PRKAG3 affected mainly muscle metabolic enzymes, indicating its possible influence on muscle metabolism with heterozygotes Ile/Val appearing different from both homozygous genotypes. The effect of CAST was smaller, affecting the quantity of one actin fragment. Dry-cured ham salt and pastiness level affected a wide variety of protein spots including metabolic enzymes, plasma proteins, chaperones and myofibrillar proteins, including protein fragments, indicating the connection with proteolysis. Pastiness was associated with salt content, reflected also by the fact that many spots were affected by both factors. Despite the absence of extreme pastiness (or low salt samples), some protein spots (actin, MHC fragment, desmin fragment) exhibited important differences in intensity according to pastiness (and salt level) suggesting they could be used as potential quality markers. 相似文献
215.
Vuk Marojevic Ismael Gomez Pere L. Gilabert Gabriel Montoro Antoni Gelonch 《Analog Integrated Circuits and Signal Processing》2012,73(2):473-482
This paper analyzes the computing resource management implications of SDR base stations implemented as SDR clouds. SDR clouds describe distributed antennas that connect to a data center for digital signal processing. The data center employs cloud computing technology, providing a virtualized computing resource pool. The service area of a single SDR cloud may be a metropolitan area with a high user density. Hence, the data center will execute thousands of SDR applications in parallel, providing wireless communications services to several radio cells. Whenever a user initiates or terminates a wireless communications session, computing resources need to be allocated or deallocated in real time. We therefore propose a hierarchical resource management. This paper justifies such an approach and analyzes different resource management strategies. The results indicate the need for strategies that can dynamically adapt to the given user traffic distribution. 相似文献
216.
Jenifer Masip Rosa Jorba Miguel Lpez-Dupla Pere Domingo Yolanda María Pacheco Graciano García-Pardo Esteban Martínez Consuelo Vilads Sergi Veloso Vernica Alba Montserrat Olona Francesc Vidal Frederic Gmez-Bertomeu Joaquim Peraire Anna Rull 《International journal of molecular sciences》2022,23(15)
Nuclear magnetic resonance (NMR)-based advanced lipoprotein tests have demonstrated that LDL and HDL particle numbers (LDL-P and HDL-P) are more powerful cardiovascular (CV) risk biomarkers than conventional cholesterol markers. Of interest, in people living with HIV (PLHIV), predictors of preclinical atherosclerosis and vascular dysfunction may be associated with impaired immune function. We previously stated that immunological non-responders (INR) were at higher CV risk than immunological responders (IR) before starting antiretroviral therapy (ART). Using Liposcale® tests, we characterized the lipoprotein profile from the same cohort of PLHIV at month 12 and month 36 after starting ART, intending to explore what happened with these indicators of CV risk during viral suppression. ART initiation dissipates the differences in lipoprotein-based CV risk markers between INR and IR, and only an increase in the number of HDL-P was found in INR + IR when compared to controls (p = 0.047). Interestingly, CD4+ T-cell counts negatively correlated with medium HDL-P concentrations at month 12 in all individuals (ρ = −0.335, p = 0.003). Longitudinal analyses showed an important increase in LDL-P and HDL-P at month 36 when compared to baseline values in both IR and INR. A proper balance between a proatherogenic and atherogenic environment may be related to the reconstitution of CD4+ T-cell count in PLHIV. 相似文献
217.
Jordi Guiteras Elena Crespo Pere Fontova Nuria Bolaos Montse Gom Esther Castao Oriol Bestard Josep M. Griny Joan Torras 《International journal of molecular sciences》2022,23(15)
Systemic lupus erythematosus is a complex autoimmune disorder mostly mediated by B-cells in which costimulatory signals are involved. This immune dysregulation can cause tissue damage and inflammation of the kidney, resulting in lupus nephritis and chronic renal failure. Given the previous experience reported with CTLA4-Ig as well as recent understanding of the PD-1 pathway in this setting, our group was encouraged to evaluate, in the NZBWF1 model, a human fusion recombinant protein (Hybri) with two domains: CTLA4, blocking the CD28—CD80 costimulatory pathway, and PD-L2, exacerbating the PD-1–PD-L2 coinhibitory pathway. After achieving good results in this model, we decided to validate the therapeutic effect of Hybri in the more severe MRL/lpr model of lupus nephritis. The intraperitoneal administration of Hybri prevented the progression of proteinuria and anti-dsDNA antibodies to levels like those of cyclophosphamide and reduced the histological score, infiltration of B-cells, T-cells, and macrophages and immune deposition in both lupus-prone models. Additionally, Hybri treatment produced changes in both inflammatory-related circulating cytokines and kidney gene expression. To summarize, both in vivo studies revealed that the Hybri effect on costimulatory-coinhibitory pathways may effectively mitigate lupus nephritis, with potential for use as a maintenance therapy. 相似文献
218.
Bryan Saldivar-Espinoza Guillem Macip Pol Garcia-Segura Júlia Mestres-Truyol Pere Puigb Adri Cereto-Massagu Gerard Pujadas Santiago Garcia-Vallve 《International journal of molecular sciences》2022,23(23)
Predicting SARS-CoV-2 mutations is difficult, but predicting recurrent mutations driven by the host, such as those caused by host deaminases, is feasible. We used machine learning to predict which positions from the SARS-CoV-2 genome will hold a recurrent mutation and which mutations will be the most recurrent. We used data from April 2021 that we separated into three sets: a training set, a validation set, and an independent test set. For the test set, we obtained a specificity value of 0.69, a sensitivity value of 0.79, and an Area Under the Curve (AUC) of 0.8, showing that the prediction of recurrent SARS-CoV-2 mutations is feasible. Subsequently, we compared our predictions with updated data from January 2022, showing that some of the false positives in our prediction model become true positives later on. The most important variables detected by the model’s Shapley Additive exPlanation (SHAP) are the nucleotide that mutates and RNA reactivity. This is consistent with the SARS-CoV-2 mutational bias pattern and the preference of some host deaminases for specific sequences and RNA secondary structures. We extend our investigation by analyzing the mutations from the variants of concern Alpha, Beta, Delta, Gamma, and Omicron. Finally, we analyzed amino acid changes by looking at the predicted recurrent mutations in the M-pro and spike proteins. 相似文献
219.
Noemí Tomsen Omar Ortega Daniel Alvarez-Berdugo Laia Rofes Pere Clav 《International journal of molecular sciences》2022,23(18)
Fluid thickening is the main compensatory strategy for patients with oropharyngeal dysphagia (OD) associated with aging or neurological diseases, and there is still no pharmacological treatment. We aimed to compare the effects of increasing bolus viscosity with that of acute stimulation with TRPV1, TRPA1 or TRPM8 agonists on the biomechanics and neurophysiology of swallow response in patients with OD. We retrospectively analyzed seven studies from our laboratory on 329 patients with OD. The effect of increasing shear viscosity up to 3682 mPa·s was compared by videofluoroscopy and pharyngeal sensory evoked potentials (pSEP) with that of adding to the bolus: capsaicin (TRPV1, 150 μM/10 μM), piperine (TRPA1/V1, 1 mM/150 μM), menthol (TRPM8, 1 mM/10 mM), cinnamaldehyde-zinc (TRPA1, 100 ppm–70 mM), citral (TRPA1, 250 ppm) or citral-isopulegol (TRPA1-TRPM8, 250 ppm–200 ppm). Fluid thickening improved the safety of swallow by 80% (p < 0.0001) by delaying bolus velocity by 20.7 ± 7.0% and time to laryngeal vestibule closure (LVC) by 23.1 ± 3.7%. Capsaicin 150μM or piperine 1 mM significantly improved safety of swallow by 50% (p < 0.01) and 57.1% (p < 0.01) by speeding time to LVC by 27.6% (p < 0.001) and 19.5% (p < 0.01) and bolus velocity by 24.8% (p < 0.01) and 16.9% (p < 0.05), respectively. Cinnamaldehyde-zinc shortened the P2 latency of pSEPs by 11.0% (p < 0.01) and reduced N2-P2 amplitude by 35% (p < 0.01). In conclusion, TRPV1 and TRPV1/A1 agonists are optimal candidates to develop new pharmacological strategies to promote the recovery of brain and swallow function in patients with chronic OD. 相似文献
220.
Letian Dai Pere Roca i Cabarrocas Huaxia Ban Zhiguo Zhang Qiang Sun Xiongjie Li Anjie Gu Wanpeng Yang Haixuan Yu Yan Shen Mingkui Wang 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(22):2208062
This work reports for the first time a highly efficient single-crystal cesium tin triiodide (CsSnI3) perovskite nanowire solar cell. With a perfect lattice structure, low carrier trap density (≈5 × 1010 cm−3), long carrier lifetime (46.7 ns), and excellent carrier mobility (>600 cm2 V−1 s−1), single-crystal CsSnI3 perovskite nanowires enable a very attractive feature for flexible perovskite photovoltaics to power active micro-scale electronic devices. Using CsSnI3 single-crystal nanowire in conjunction with highly conductive wide bandgap semiconductors as front-surface-field layers, an unprecedented efficiency of 11.7% under AM 1.5G illumination is achieved. This work demonstrates the feasibility of all-inorganic tin-based perovskite solar cells via crystallinity and device-structure improvement for the high-performance, and thus paves the way for the energy supply to flexible wearable devices in the future. 相似文献