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排序方式: 共有234条查询结果,搜索用时 31 毫秒
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John J. Guardiola Josiah E. Hardesty Juliane I. Beier Russell A. Prough Craig J. McClain Matthew C. Cave 《International journal of molecular sciences》2021,22(10)
Background: High-level occupational vinyl chloride (VC) exposures have been associated with hepatic hemangiosarcoma, which typically develops following a long latency period. Although VC is genotoxic, a more comprehensive mode of action has not been determined and diagnostic biomarkers have not been established. The purpose of this study is to address these knowledge gaps through plasma metabolomics. Methods: Plasma samples from polyvinyl chloride polymerization workers who developed hemangiosarcoma (cases, n = 15) and VC exposure-matched controls (n = 17) underwent metabolomic analysis. Random forest and bioinformatic analyses were performed. Results: Cases and controls had similar demographics and routine liver biochemistries. Mass spectroscopy identified 606 known metabolites. Random forest analysis had an 82% predictive accuracy for group classification. 60 metabolites were significantly increased and 44 were decreased vs. controls. Taurocholate, bradykinin and fibrin degradation product 2 were up-regulated by greater than 80-fold. The naturally occurring anti-angiogenic phenol, 4-hydroxybenzyl alcohol, was down-regulated 5-fold. Top affected ontologies involved: (i) metabolism of bile acids, taurine, cholesterol, fatty acids and amino acids; (ii) inflammation and oxidative stress; and (iii) nicotinic cholinergic signaling. Conclusions: The plasma metabolome was differentially regulated in polyvinyl chloride workers who developed hepatic hemangiosarcoma. Ontologies potentially involved in hemangiosarcoma pathogenesis and candidate biomarkers were identified. 相似文献
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Felix Schmutzler Christopher Zschiesche Juliane Titus David Poppitz Jens Freiding Rainer Rakoczy Andreas Reitzmann Roger Gläser 《化学,工程师,技术》2021,93(6):981-989
The hydroisomerization of two long-chain n-alkane mixtures was investigated over bifunctional Pt/H-ZSM-5 catalysts before and after dealumination of preshaped zeolite/binder pellets. The hydroisomerization over the dealuminated catalysts leads to more isomers and less cracking products. Consequently, higher ratios of multi- to mono-branched isomerization products are formed as expected for large- rather than medium-pore zeolites. This indicates a higher availability of space in the vicinity of the active sites and provides an attractive route to make medium-pore zeolites suitable for upgrading higher boiling hydrocarbon feeds. 相似文献
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A two-layer architecture for dynamic real-time optimization (or nonlinear modelpredictive control (NMPC) with an economic objective) is presented, where the solution of the dynamic optimization problem is computed on two time-scales. On the upper layer, a rigorous optimization problem is solved with an economic objective function at a slow time-scale, which captures slow trends in process uncertainties. On the lower layer, a fast neighboring-extremal controller is tracking the trajectory in order to deal with fast disturbances acting on the process. Compared to a single-layer architecture, the two-layer architecture is able to address control systems with complex models leading to high computational load, since the rigorous optimization problem can be solved at a slower rate than the process sampling time. Furthermore, solving a new rigorous optimization problem is not necessary at each sampling time if the process has rather slow dynamics compared to the disturbance dynamics. The two-layer control strategy is illustrated with a simulated case study of an industrial polymerization process. 相似文献
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Sara S. Santos Alessandra Lorenzoni Luana M. Ferreira Juliane Mattiazzi Andréa I.H. Adams Laura B. Denardi Sydney H. Alves Scheila R. Schaffazick Letícia Cruz 《Materials science & engineering. C, Materials for biological applications》2013,33(3):1389-1394
Clotrimazole is a common choice for the treatment of vulvovaginal infections, but its low solubility and some side effects pose a challenge to its application. This work evaluated the feasibility to formulate clotrimazole-loaded cationic nanocapsules using Eudragit® RS100 and medium chain triglycerides as polymer and oily core, respectively, by the method of interfacial deposition of a preformed polymer. The physicochemical characteristics of nanocapsule formulations were evaluated at 0 day and 60 days after preparation. Particle size, zeta potential, polydispersity index, pH and drug content were stable during this period. In addition, nanocapsules were able to protect clotrimazole from photodegradation under UV radiation. By the dialysis bag diffusion technique, the nanosized formulations showed prolonged release of clotrimazole by anomalous transport and first order kinetics. A microbiological study was carried out by the microdilution method and showed that nanocapsules (mean size: 144 nm; zeta potential: + 12 mV) maintained the antifungal activity of clotrimazole against Candida albicans and Candida glabrata strains susceptible and resistant to fluconazole. 相似文献
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Project risk management is recognized as essential in order to cope with the challenges arising from the environment. Literature suggests a portfolio-wide perspective for managing risks in project portfolios. However, research on risk management and its success in a project portfolio context is scarce. This study examines how portfolio risk management influences project portfolio success. Using a sample of 176 firms, this study provides evidence that portfolio risk identification, the formalization of the portfolio risk management process, and risk management culture directly influence risk transparency, whereas risk prevention, risk monitoring, and the integration of risk management into project portfolio management are directly connected to risk coping capacity. The findings also suggest that both risk transparency and risk coping capacity have a direct impact on project portfolio success. However, the results did not confirm the hypothesis that risk transparency and risk coping capacity have a complementary effect on success. Implications for scholars and project portfolio managers are discussed. 相似文献
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Andreas Zehnsdorf Norman Stock Juliane Richter Michael Blumberg Roland A. Müller 《化学,工程师,技术》2016,88(8):1138-1144
There is increasing interest worldwide in the decentralized treatment of gray water. Since ground‐level areas are generally costly, gray‐water treatment can also be carried out using helophyte mats on the roofs of buildings as an alternative. Alongside the water treatment itself, this process also has a positive effect on the indoor climate in the building. In a test carried out under realistic conditions, it was shown that a helophyte mat with a root‐layer depth of 0.1 m and with hydraulic loads per unit up to 15 L m?2d?1 is suitable for treating typical gray water from a residential building. 相似文献
9.
Dr. Tessa Lühmann Valerie Spieler Dr. Vera Werner Dr. Marie‐Gabrielle Ludwig Dr. Juliane Fiebig Prof. Dr. Thomas D. Mueller Prof. Dr. Dr. Lorenz Meinel 《Chembiochem : a European journal of chemical biology》2016,17(22):2123-2128
Driving macrophage (M?) polarization into the M2 phenotype provides potential against inflammatory diseases. Interleukin‐4 (IL‐4) promotes polarization into the M2‐M? phenotype, but its systemic use is constrained by dose‐limiting toxicity. Consequently, we developed IL‐4‐decorated surfaces aiming at sustained and localized activity. IL‐4 muteins were generated by genetic code expansion; Lys42 was replaced by unnatural amino acids (uAAs). Both muteins showed cell‐stimulation ability and binding affinity to IL4Rα similar to those of wt‐IL‐4. Copper‐catalyzed (CuAAC) and copper‐free strain‐promoted (SPAAC) 1,3‐dipolar azide–alkyne cycloadditions were used to site‐selectively anchor IL‐4 to agarose surfaces. These surfaces had sustained IL‐4 activity, as demonstrated by TF‐1 cell proliferation and M2, but not M1, polarization of M‐CSF‐generated human M?. The approach provides a blueprint for the engineering of cytokine‐activated surfaces profiled for sustained and spatially controlled activity. 相似文献
10.
Cleaning capacity of octenidine as root canal irrigant: A scanning electron microscopy study 下载免费PDF全文
Hernán Coaguila‐Llerena Virgínia Stefanini da Silva Mario Tanomaru‐Filho Juliane Maria Guerreiro Tanomaru Gisele Faria 《Microscopy research and technique》2018,81(6):523-527
The aim of this study was to assess the cleaning capacity of the octenidine hydrochloride (OCT) used as root canal irrigant by scanning electron microscopy (SEM) analysis. Sixty human unirradicular extracted teeth were randomly distributed in 6 groups (n = 10) according to irrigant solutions which were used during root canal preparation: G1, 0.1% OCT; G2, 2% chlorhexidine (CHX); G3, 2.5% sodium hypochlorite (NaOCl); G4, OCT + 17% ethylenediaminetetraacetic acid (EDTA); G5, 2.5% NaOCl + 17% EDTA and G6, distilled water. All specimens were instrumented with ProTaper system up to F4. Teeth were sectioned and prepared for SEM. The smear layer was evaluated using a 5‐score system and the data were analyzed by Kruskal–Wallis and Dunn (α = 0.05). In all root canal thirds there was no significant difference between OCT, CHX, NaOCl, and water groups (p > .05), and these groups showed higher smear layer values than NaOCl + EDTA and OCT + EDTA groups (p < .05). There was no significant difference between NaOCl + EDTA and OCT + EDTA groups (p > .05). It was concluded that OCT used as a single root canal irrigant presented poor cleaning capacity and could be used in association with a final irrigation with EDTA to obtain smear layer removal. 相似文献