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891.
Combined use of Pronase E and a fungal extract (Penicillium aurantiogriseum) to potentiate the sensory characteristics of dry fermented sausages 总被引:1,自引:0,他引:1
A combination of an extract of Penicillium aurantiogriseum and Pronase E was used in an attempt to enhance the sensory characteristics of dry fermented sausages, specifically, a salami-like one named "salchichón". The addition of Pronase E alone (600 units/kg) produced a rise in free amino acids and biogenic amines and also an increase in the ammonia content. Addition of the protease and fungal extract (100.87 mg protein/kg of mixture) brought about a decrease in the level of free amino acids and a larger increase in the ammonia content than the batch added with only Pronase E. There was also an increase in the amount of specific volatile compounds such as 2- and 3-methylbutanal, 2- and 3-methylpropanal and 2- and 3-methyl-1-butanol produced by the breakdown of amino acids in these fermented sausages. Values of pH, a(w) and dry matter were not affected by addition of the protease or fungal extract. In contrast, addition of Pronase E produced a notable change in the textural characteristics, reducing the hardness, cohesiveness, gumminess, chewiness and cutting force. Sensory analysis showed that fermented sausages manufactured with Pronase E and Penicillium aurantiogriseum extract had better odour, flavour, texture and, as a consequence, better general acceptability. 相似文献
892.
Quasiperiodic phases (quasicrystals) have been found in numerous alloy systems of aluminum with transition metals (TM) between about 60 and 85 at.% Al. In binary Al–TM systems only metastable quasicrystals were observed, while in several ternary systems containing Cu, Ni or Pd the quasicrystals are stable. Many stable and metastable periodic phases formed in these compositional ranges exhibit structural relations to quasicrystals. Studies of these phenomenona have stimulated extensive investigation or revision of the high-Al regions of the ternary alloy systems belonging to the Al–Cu–TM, Al–Ni–TM and Al–Pd–TM groups. These studies are reviewed here. 相似文献
893.
894.
Blint Barth Dvid K. Jsz Tamara Horvth Bence Barth Gergely Marti Gerda Strifler Gabriella Varga Lilla Sndor Domonkos Pernyi Szabolcs Tallsy Tibor Donka Pter Jvor Mihly Boros Petra Hartmann 《International journal of molecular sciences》2022,23(9)
Despite their clinical effectiveness, a growing body of evidence has shown that many classes of antibiotics lead to mitochondrial dysfunction. Ceftriaxone and Rifaximin are first choice perioperative antibiotics in gastrointestinal surgery targeting fundamental processes of intestinal bacteria; however, may also have negative consequences for the host cells. In this study, we investigated their direct effect on mitochondrial functions in vitro, together with their impact on ileum, colon and liver tissue. Additionally, their impact on the gastrointestinal microbiome was studied in vivo, in a rat model. Rifaximin significantly impaired the oxidative phosphorylation capacity (OxPhos) and leak respiration in the ileal mucosa, in line with increased oxidative tissue damage and histological changes following treatment. Ceftriaxone prophylaxis led to similar changes in the colon mucosa. The composition and diversity of bacterial communities differed extensively in response to antibiotic pre-treatment. However, the relative abundances of the toxin producing species were not increased. We have confirmed the harmful effects of prophylactic doses of Rifaximin and Ceftriaxone on the intestinal mucosa and that these effects were related to the mitochondrial dysfunction. These experiments raise awareness of mitochondrial side effects of these antibiotics that may be of clinical importance when evaluating their adverse effects on bowel mucosa. 相似文献
895.
Tamara Bakuradze Roman Lang Thomas Hofmann Herbert Stiebitz Gerhard Bytof Ingo Lantz Matthias Baum Gerhard Eisenbrand Christine Janzowski 《Molecular nutrition & food research》2010,54(12):1734-1743
Scope: Epidemiological studies suggest that coffee can reduce the risk of degenerative diseases such as diabetes type 2, cardiovascular disease and cancer. These beneficial effects have partly been attributed to the antioxidant activity of coffee. We determined composition and antioxidant potential of differentially roasted coffee extracts and investigated the impact of selected original constituents and roast products. Methods and results: Parameters studied were direct antioxidant activity (trolox equivalent antioxidant capacity/oxygen radical absorbing capacity), cellular reactive oxygen species (ROS) level, DNA damage and protein expression of NAD(P)H: quinone oxidoreductase, γ‐glutamylcysteine ligase and glutathione reductase in HT‐29/Caco‐2 cells at 24‐h incubation. All extracts showed distinct direct antioxidant activity: medium roasts>light roast AB1 (caffeoylquinic acid (CQA)‐rich Arabica Brazil extract); dark roast AB2 (N‐methylpyridinium (NMP)‐rich Arabica Brazil extract), and diminished t‐butylhydroperoxide‐induced ROS level in HT‐29 cells (AB2>medium roasts>AB1). NAD(P)H:quinone oxidoreductase 1 expression and γ‐glutamylcysteine ligase expression were distinctly induced by AB1 and 5‐CQA, but not by AB2 and NMP. 5‐CQA and caffeic acid exhibited highest trolox equivalent antioxidant capacity/oxygen radical absorbing capacity values (5‐CQA: 1.3/3.5 mM and caffeic acid: 1.3/3.9 mM trolox); ROS level was distinctly diminished by 5‐CQA (≥3 μM), catechol (30 μM) and trigonelline (≥30 μM), whereas menadione‐induced DNA damage in Caco‐2 cells was reduced by NMP compounds (1–30 μM). Conclusion: The results emphasize that both original constituents and roast products contribute to the cellular antioxidant effectiveness of coffee. 相似文献
896.
Optimization of ultrasound‐assisted extraction of grape‐seed oil to enhance process yield and minimize free radical formation 下载免费PDF全文
897.
Lucas Diniz Giraldeli Bruna Constante Fonseca Valeria Reginatto 《International Journal of Hydrogen Energy》2018,43(49):22159-22169
Fermentative hydrogen production allows the use of renewable biomasses as feedstocks. However, biomass saccharification results not only in carbohydrates, but also in products that can inhibit fermentation. Although biomass hydrolysates contain mixtures of inhibitors, most studies are performed with a single inhibitor. This study evaluates how 5-hydroxymethylfurfural (HMF, 0.60 g/L), levulinic acid (LA, 2.10 g/L), and/or formic acid (FA, 0.80 g/L) mixtures affect two H2-producing clostridia, Clostridium beijerinckii Br21 and Clostridium acetobutylicum ATCC 824. Fermentation assays with and without (control) the inhibitors helped to calculate the specific H2 production, substrate consumption, and bacterial cell growth rates for Clostridium beijerinckii Br21 or Clostridium acetobutylicum ATCC 824. HMF + AL, HMF + AF, AL + AF, and HMF + AL + AF mixtures inhibited H2 production by C. beijerinckii Br21 by 58.7, 60.0, 46.9, and 83.0%, respectively, and by C. acetobutylicum ATCC 824 by 68.1, 71.4, 58.2, and 89.0%, respectively. Clostridium acetobutylicum ATCC 824 metabolized HMF more efficiently. However, organic acids and their combination with HMF inhibited H2 production by C. beijerinckii Br21 to a lesser extent, which highlighted that this microorganism is robust for H2 production from biomass hydrolysates. 相似文献
898.
Laura Mourino-Alvarez Nerea Corbacho-Alonso Tamara Sastre-Oliva Cecilia Corros-Vicente Jorge Solis Teresa Tejerina Luis R. Padial Maria G. Barderas 《International journal of molecular sciences》2021,22(12)
Aortic stenosis (AS) and diabetes mellitus (DM) are both progressive diseases that if left untreated, result in significant morbidity and mortality. Several studies revealed that the prevalence of DM is substantially higher in patients with AS and, thus, the progression from mild to severe AS is greater in those patients with DM. DM and common comorbidities associated with both diseases, DM and AS, increase patient management complexity and make aortic valve replacement the only effective treatment. For that reason, a better understanding of the pathogenesis underlying both these diseases and the relationships between them is necessary to design more appropriate preventive and therapeutic approaches. In this review, we provided an overview of the main aspects of the relationship between AS and DM, including common comorbidities and risk factors. We also discuss the established treatments/therapies in patients with AS and DM. 相似文献
899.
Preethi Bala Balakrishnan Niccolò Silvestri Tamara Fernandez-Cabada Federica Marinaro Soraia Fernandes Sergio Fiorito Mario Miscuglio David Serantes Sergiu Ruta Karen Livesey Ondrej Hovorka Roy Chantrell Teresa Pellegrino 《Advanced materials (Deerfield Beach, Fla.)》2020,32(45):2003712
Nanoparticle-based magnetic hyperthermia is a well-known thermal therapy platform studied to treat solid tumors, but its use for monotherapy is limited due to incomplete tumor eradication at hyperthermia temperature (45 °C). It is often combined with chemotherapy for obtaining a more effective therapeutic outcome. Cubic-shaped cobalt ferrite nanoparticles (Co–Fe NCs) serve as magnetic hyperthermia agents and as a cytotoxic agent due to the known cobalt ion toxicity, allowing the achievement of both heat and cytotoxic effects from a single platform. In addition to this advantage, Co–Fe NCs have the unique ability to form growing chains under an alternating magnetic field (AMF). This unique chain formation, along with the mild hyperthermia and intrinsic cobalt toxicity, leads to complete tumor regression and improved overall survival in an in vivo murine xenograft model, all under clinically approved AMF conditions. Numerical calculations identify magnetic anisotropy as the main Co–Fe NCs’ feature to generate such chain formations. This novel combination therapy can improve the effects of magnetic hyperthermia, inaugurating investigation of mechanical behaviors of nanoparticles under AMF, as a new avenue for cancer therapy. 相似文献
900.
Yazeed Yasin Ghadi Nida Khalid Suliman A. Alsuhibany Tamara al Shloul Ahmad Jalal Jeongmin Park 《计算机、材料和连续体(英文)》2022,72(2):2597-2615
Human Activity Recognition (HAR) plays an important role in life care and health monitoring since it involves examining various activities of patients at homes, hospitals, or offices. Hence, the proposed system integrates Human-Human Interaction (HHI) and Human-Object Interaction (HOI) recognition to provide in-depth monitoring of the daily routine of patients. We propose a robust system comprising both RGB (red, green, blue) and depth information. In particular, humans in HHI datasets are segmented via connected components analysis and skin detection while the human and object in HOI datasets are segmented via saliency map. To track the movement of humans, we proposed orientation and thermal features. A codebook is generated using Linde-Buzo-Gray (LBG) algorithm for vector quantization. Then, the quantized vectors generated from image sequences of HOI are given to Artificial Neural Network (ANN) while the quantized vectors generated from image sequences of HHI are given to K-ary tree hashing for classification. There are two publicly available datasets used for experimentation on HHI recognition: Stony Brook University (SBU) Kinect interaction and the University of Lincoln's (UoL) 3D social activity dataset. Furthermore, two publicly available datasets are used for experimentation on HOI recognition: Nanyang Technological University (NTU) RGB-D and Sun Yat-Sen University (SYSU) 3D HOI datasets. The results proved the validity of the proposed system. 相似文献