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81.
82.
Sílvia Cristina Sobottka Rolim de Moura Paulo Eduardo da Rocha Tavares Sílvia Pimentel Marconi Germer Alba Lucia Andrade Coelho Nisida Adriana Barreto Alves Alexandre Saikali Kanaan 《Food and Bioprocess Technology》2012,5(6):2488-2496
The objective of this study was to monitor the stability of anthocyanin and phenolic compounds contained in two formulations of blackberry jam (traditional and low-sugar) during storage. For that purpose, jams were prepared with varying amounts of hydrocolloids and investigated as to pH, total soluble solids, water activity, total acidity, total anthocyanins and total polyphenols. In order to accompany and assess the levels of phenolic compounds and colour (L*, a* and b*) changes, the samples were stored for 180 days at two different temperatures (10 and 25 °C). The Arrhenius model was used to determine the relationship between the reaction rate (k) at the different storage temperatures, yielding activation energy values of 19 and 12 kcal/mol and Q 10 values of 3.0 and 2.0 for traditional and low-sugar jams, respectively. The results show that by the end of the storage time investigated, the anthocyanin compounds had been partially degraded, with the greatest loss being observed in traditional jam stored at 25 °C. Colour stability was also lower in traditional jam as compared to the low-sugar product. 相似文献
83.
Lipid kinases and phosphatases play essential roles in signal transduction processes involved in cytoskeletal rearrangement,
membrane trafficking, and cellular differentiation. Phosphatidic acid (PtdOH) is an important mediator lipid in eukaryotic
cells, but little is known regarding its regulation in the parasite Trypanosoma cruzi, an agent of Chagas disease. In order to clarify the relationship between PtdOH metabolism and developmental stages of T. cruzi, epimastigotes in culture were subjected to hyperosmotic stress (~1,000 mOsm/L), mimicking the environment in the rectum
of vector triatomine bugs. These experimental conditions resulted in differentiation to an intermediate form between epimastigotes
and trypomastigotes. Morphological changes of epimastigotes were correlated with an increase in PtdOH mass accomplished by
increased enzyme activity of diacylglycerol kinase (DAGK, E.C. 2.7.1.107) and concomitant decreased activity of phosphatidate
phosphatases type 1 and type 2 (PAP1, PAP2, E.C. 3.1.3.4). Our results indicate progressive increases of PtdOH levels during
the differentiation process, and suggest that the regulation of PtdOH metabolism is an important mechanism in the transition
from T. cruzi epimastigote to intermediate form. 相似文献
84.
Dr. Cristina Tintori Ilaria Laurenzana Francesco La Rocca Dr. Federico Falchi Prof. Fabio Carraro Alba Ruiz Prof. José A. Esté Miroslava Kissova Dr. Emmanuele Crespan Prof. Giovanni Maga Prof. Mariangela Biava Dr. Chiara Brullo Prof. Silvia Schenone Prof. Maurizio Botta 《ChemMedChem》2013,8(8):1353-1360
Hematopoietic cell kinase (Hck) is a member of the Src family of non‐receptor protein tyrosine kinases. High levels of Hck are associated with drug resistance in chronic myeloid leukemia. Furthermore, Hck activity has been connected with HIV‐1. Herein, structure‐based drug design efforts were aimed at identifying novel Hck inhibitors. First, an in‐house library of pyrazolo[3,4‐d]pyrimidine derivatives, which were previously shown to be dual Abl and c‐Src inhibitors, was analyzed by docking studies within the ATP binding site of Hck to select the best candidates to be tested in a cell‐free assay. Next, the same computational protocol was applied to screen a database of commercially available compounds. As a result, most of the selected compounds were found active against Hck, with Ki values ranging from 0.14 to 18.4 μM , confirming the suitability of the computational approach adopted. Furthermore, selected compounds showed an interesting antiproliferative activity profile against the human leukemia cell line KU‐812, and one compound was found to block HIV‐1 replication at sub‐toxic concentrations. 相似文献
85.
M. Melgosa M. M. Prez E. Hita M. J. Moyano J. Alba F. J. Heredia 《Journal of the American Oil Chemists' Society》2000,77(10):1093-1100
Twenty experienced observers with nondefective color vision judged 27 virgin olive oil samples within an acceptable color
range, using the bromthymol blue (BTB) method, under controlled observation conditions (daylight source with a correlated
color temperature of 6500 K, and standard gray back-ground). On the average, 44.8% of the observers agreed in their selections
of the BTB standard solution matching a given oil sample, and this percentage increased to 88.2% considering ±one step in
the two dimensions (pH and concentration) of the BTB scale. On the average, the lowest color difference between oil samples
and available BTB solutions was 6.6 Commission Internationale de l'éclairage 1976-(L*a*b*) (CIELAB) units, but this color difference was approximately two times greater for the color difference between oil samples
and BTB solutions selected by our observers. The colors of the BTB standard solutions in the CIELAB space are not uniformly
distributed, and thus one step in pH or concentration is equivalent to CIELAB color differences varying in a wide range (1.7–13.5
and 1.7–26.3 CIELAB units, respectively). From these values, indicating low precision, accuracy, and uniformity, some suggestions
are made for future improvements of the current BTB method. 相似文献
86.
Poly (2-ethyl-2-oxazoline) (PEOZ) is one of the commercial members of a family of materials that have shown significant application
potential in a large number of technological contexts, most of them related with biomedical problems where water-soluble polymer
systems are highly desirable. Polymeric fibers with diameters in the 200–800 nm range of PEOZ were prepared by electrospinning
of its water solutions. Processing and solution parameters effects on the morphology and the diameter of the fibers were investigated.
SEM results showed that the polymer concentration and the applied voltage might be used as variables to control the morphology
and the diameter of the electrospun fibers. Solutions of the same polymer in other two organic solvents (N,N-dimethylformamide (DMF) and tetrahydrofurane (THF)) were also processed by the same technique but without the promising results
of the water solutions. 相似文献
87.
María Illescas María E. Morn-Diez ngel Emilio Martínez de Alba Rosa Hermosa Enrique Monte 《International journal of molecular sciences》2022,23(12)
Eight Trichoderma strains were evaluated for their potential to protect wheat seedlings against severe (no irrigation within two weeks) water stress (WS). Considering the plant fresh weight and phenotype, T. asperellum T140, which displays 1-aminocyclopropane-1-carboxylic acid deaminase activity and which is able to produce several phytohormones, was selected. The molecular and biochemical results obtained from 4-week-old wheat seedlings linked T140 application with a downregulation in the WS-response genes, a decrease in antioxidant activities, and a drop in the proline content, as well as low levels of hydrogen peroxide and malondialdehyde in response to severe WS. All of these responses are indicative of T140-primed seedlings having a higher tolerance to drought than those that are left untreated. A greenhouse assay performed under high nitrogen fertilization served to explore the long-term effects of T140 on wheat plants subjected to moderate (halved irrigation) WS. Even though all of the plants showed acclimation to moderate WS regardless of T140 application, there was a positive effect exerted by T. asperellum on the level of tolerance of the wheat plants to this stress. Strain T140 modulated the expression of a plant ABA-dependent WS marker and produced increased plant superoxide dismutase activity, which would explain the positive effect of Trichoderma on increasing crop yields under moderate WS conditions. The results demonstrate the effectiveness of T. asperellum T140 as a biostimulant for wheat plants under WS conditions, making them more tolerant to drought. 相似文献
88.
A parallel micro evolutionary algorithm for heterogeneous computing and grid scheduling 总被引:1,自引:0,他引:1
This work presents a novel parallel micro evolutionary algorithm for scheduling tasks in distributed heterogeneous computing and grid environments. The scheduling problem in heterogeneous environments is NP-hard, so a significant effort has been made in order to develop an efficient method to provide good schedules in reduced execution times. The parallel micro evolutionary algorithm is implemented using MALLBA, a general-purpose library for combinatorial optimization. Efficient numerical results are reported in the experimental analysis performed on both well-known problem instances and large instances that model medium-sized grid environments. The comparative study of traditional methods and evolutionary algorithms shows that the parallel micro evolutionary algorithm achieves a high problem solving efficacy, outperforming previous results already reported in the related literature, and also showing a good scalability behavior when facing high dimension problem instances. 相似文献
89.
Rolando Roque-Malherbe Alba N. Costa-Hernandez Christymarie Rivera-Maldonado Frances N.Lugo-Alvarado Ramon Polanco-Estrella 《材料科学与工程:中英文B版...》2013,(5):263-280
Carbon dioxide (CO2) adsorption is an important adsorbent characterization method and a significant industrial process. In separation and recovery technology, the adsorption of the CO2 is important to reduce the concentration of this gas considered as one of the greenhouse gases. Natural zeolites, particularly clinoptilolite, are widely applied as adsorbents. In this regard, in the present research, the structure, composition and morphology of modified with hexafluorosilicate (HFSi) and orthophosphoric acid (H3PO4) clinoptilolites were investigated by characterizations and measurements made with, X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDAX) and gravimetric adsorption. Additionally, the surface Chemistry of the modified clinoptilolites was analyzed by applying diffuse reflectance fourier transform infrared spectrometry (DRIFTS). Further, the interaction of CO2 within the adsorption space of these modified clinoptilolites and a synthetic ZSM-5 zeolite was studied with the help of adsorption measurements. After all, an appropriate theoretical methodology for the analysis of the XRD and adsorption data was applied. The calculated cell parameters of the tested are similar to those reported for a typical clinoptilolite of: a = 17.662 A, b = 17.911A, c = 7.407 ~ and fl = 116.40 The resolution of the TGA derivative profiles indicated the presence of two steps for water release, one of them represents the loss of majority of the water present in the micropores. This was evidenced as a broad peak centered at about 50℃ for the CSW-HFSi-0.1, but at 100 ℃ for the samples CSW-HFSi-0.4. The SEM micrographs corresponding to the modified clinoptilolites, was evidenced that the CSW zeolite shows secondary particles exhibiting diameters from 3 to 40 μm, formed by primary clinoptilolite crystallites showing a crystallite size, φ = 40 nm. The EDAX elemental analysis it can be demonstrated that the exchange process replaced about 85% of the charge compensating ions. The DRIFT spectra of the modified clinoptilolites, specifically, CSW-HFSi-0.1, show a narrow band at about: 3,740 cm-1 corresponding to terminal silanol groups (Si-OH) and a band 3,600-3,650 cm1 resulting from extra-framework AI-OH. With the precision of the measured micropore volumes related to the excellent fitting of the adsorption data by the D-R isotherm equation, it can be affirm that carbon adsorption took only place in the micropore region. The isosteric heat of adsorption calculated for the modified clinoptilolites was greater than those values reported of ZSM-5 zeolite, particle packing silica, dealuminated Y zeolite (DAY) Cd, Zn and Ni-nitroprussides and Cu-nitroprusside and a Ni-MOF. With the obtained result it can be concluded that the modified clinoptilolites with HFSi showed a quality as adsorbent comparable to commercial synthetic zeolites. 相似文献
90.
Júlia Faura Laura Ramiro Alba Simats Feifei Ma Anna Penalba Teresa Gasull Anna Rosell Joan Montaner Alejandro Bustamante 《International journal of molecular sciences》2022,23(15)
After stroke and other brain injuries, there is a high incidence of respiratory complications such as pneumonia or acute lung injury. The molecular mechanisms that drive the brain-lung interaction post-stroke have not yet been elucidated. We performed transient middle cerebral artery occlusion (MCAO) and sham surgery on C57BL/6J mice and collected bronchoalveolar lavage fluid (BALF), serum, brain, and lung homogenate samples 24 h after surgery. A 92 proteins-panel developed by Olink Proteomics® was used to analyze the content in BALF and lung homogenates. MCAO animals had higher protein concentration levels in BALF than sham-controls, but these levels did not correlate with the infarct volume. No alteration in alveolar-capillary barrier permeability was observed. A total of 12 and 14 proteins were differentially expressed between the groups (FDR < 0.1) in BALF and lung tissue homogenates, respectively. Of those, HGF, TGF-α, and CCL2 were identified as the most relevant to this study. Their protein expression patterns were verified by ELISA. This study confirmed that post-stroke lung damage was not associated with increased lung permeability or cerebral ischemia severity. Furthermore, the dysregulation of HGF, TGF-α, and CCL2 in BALF and lung tissue after ischemia could play an important role in the molecular mechanisms underlying stroke-induced lung damage. 相似文献