全文获取类型
收费全文 | 507篇 |
免费 | 36篇 |
专业分类
电工技术 | 14篇 |
化学工业 | 171篇 |
金属工艺 | 20篇 |
机械仪表 | 14篇 |
建筑科学 | 9篇 |
能源动力 | 23篇 |
轻工业 | 64篇 |
水利工程 | 2篇 |
无线电 | 45篇 |
一般工业技术 | 99篇 |
冶金工业 | 37篇 |
原子能技术 | 1篇 |
自动化技术 | 44篇 |
出版年
2023年 | 4篇 |
2022年 | 39篇 |
2021年 | 49篇 |
2020年 | 23篇 |
2019年 | 20篇 |
2018年 | 12篇 |
2017年 | 26篇 |
2016年 | 21篇 |
2015年 | 16篇 |
2014年 | 20篇 |
2013年 | 29篇 |
2012年 | 23篇 |
2011年 | 30篇 |
2010年 | 14篇 |
2009年 | 30篇 |
2008年 | 22篇 |
2007年 | 13篇 |
2006年 | 15篇 |
2005年 | 14篇 |
2004年 | 15篇 |
2003年 | 13篇 |
2002年 | 14篇 |
2001年 | 2篇 |
2000年 | 7篇 |
1999年 | 1篇 |
1998年 | 9篇 |
1997年 | 7篇 |
1996年 | 8篇 |
1995年 | 6篇 |
1994年 | 5篇 |
1993年 | 5篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 5篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1976年 | 6篇 |
排序方式: 共有543条查询结果,搜索用时 18 毫秒
531.
Suitability of the milk of native breeds of cows from low‐input farms for cheese production,including rennet curd texture
下载免费PDF全文
![点击此处可从《International Journal of Dairy Technology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Anna Wolanciuk Joanna Barłowska Zygmunt Litwińczuk Mariusz Florek 《International Journal of Dairy Technology》2016,69(4):585-591
The cheesemaking suitability of the milk of native cow breeds [Polish Red (RP) and White‐Backed (BG)] raised on low‐input farms was assessed. The milk of Polish Holstein‐Friesian cows raised in an intensive system constituted the reference group. Chemical composition, pH, rennet coagulation time, fat dispersion and curd texture were determined. The cows on the low‐input farms produced over 40% less milk, but with higher (P ≤ 0.01) fat content, shorter coagulation time by over 2 min and lower (P ≤ 0.05) fat dispersion. The curds from this milk were significantly springier, more cohesive and harder. The best milk indices were obtained for the RP cows. 相似文献
532.
The study focused on partial replacement in gluten-free breads of corn starch with tapioca and corn resistant starch preparations. The use of resistant starch resulted in the increase of storage and loss moduli of the dough, and the lowering of loss tangent, which indicates its more elastic character. The incorporation of resistant starch reduced creep and recovery compliance and elevated zero shear viscosity. Modified doughs displayed higher starch gelatinization temperatures and lower viscosities that were proportional to the share of RS. It was found that the loaves baked with the share of resistant starch had less hard crumb than bread without RS addition. The crumb hardness diminished with the increasing amount of applied RS preparation. The addition of resistant starch raised total dietary fibre, by up to 89%, as compared to control (bread without RS addition). The most pronounced change was observed for insoluble dietary fibre (increase 137%), while only slight increase was found for its soluble fraction (18%). 相似文献
533.
Andrzej Hudecki Dorota yko-Morawska Anna Kasprzycka Alicja Kazek-Ksik Wirginia Likus Jolanta Hybiak Kornelia Jankowska Aleksandra Kolano-Burian Patryk Wodarczyk Weronika Wolany Jarosaw Markowski Wojciech Maziarz Iwona Niedzielska Wojciech Pakiea Mariusz Nowak Marek J. os 《International journal of molecular sciences》2022,23(9)
The specific combinations of materials and dopants presented in this work have not been previously described. The main goal of the presented work was to prepare and compare the different properties of newly developed composite materials manufactured by sintering. The synthetic- (SHAP) or natural- (NHAP) hydroxyapatite serves as a matrix and was doped with: (i) organic: multiwalled carbon nanotubes (MWCNT), fullerenes C60, (ii) inorganic: Cu nanowires. Research undertaken was aimed at seeking novel candidates for bone replacement biomaterials based on hydroxyapatite—the main inorganic component of bone, because bone reconstructive surgery is currently mostly carried out with the use of autografts; titanium or other non-hydroxyapatite -based materials. The physicomechanical properties of the developed biomaterials were tested by Scanning Electron Microscopy (SEM), Dielectric Spectroscopy (BSD), Nuclear Magnetic Resonance (NMR), and Differential Scanning Calorimetry (DSC), as well as microhardness using Vickers method. The results showed that despite obtaining porous sinters. The highest microhardness was achieved for composite materials based on NHAP. Based on NMR spectroscopy, residue organic substances could be observed in NHAP composites, probably due to the organic structures that make up the tooth. Microbiology investigations showed that the selected samples exhibit bacteriostatic properties against Gram-positive reference bacterial strain S. epidermidis (ATCC 12228); however, the property was much less pronounced against Gram-negative reference strain E. coli (ATCC 25922). Both NHAP and SHAP, as well as their doped derivates, displayed in good general compatibility, with the exception of Cu-nanowire doped derivates. 相似文献
534.
Mateusz Kciuk Somdutt Mujwar Anna Szymanowska Beata Marciniak Karol Bukowski Mariusz Mojzych Renata Kontek 《International journal of molecular sciences》2022,23(11)
Pyrazolo[4,3-e]tetrazolo[1,5-b][1,2,4]triazine sulfonamides constitute a novel class of heterocyclic compounds with broad biological activity, including anticancer properties. Investigated in this study, MM-compounds (MM134, MM136, MM137, and MM139) exhibited cytotoxic and proapoptotic activity against cancer cell lines (BxPC-3, PC-3, and HCT-116) in nanomolar concentrations without causing cytotoxicity in normal cells (L929 and WI38). In silico predictions indicate that tested compounds exhibit favorable pharmacokinetic profiles and may exert anticancer activity through the inhibition of BTK kinase, the AKT-mTOR pathway and PD1-PD-L1 interaction. Our findings point out that these sulfonamide derivatives may constitute a source of new anticancer drugs after optimization. 相似文献
535.
Katarzyna Wegrzynowska-Drzymalska Kinga Mylkie Pawel Nowak Dariusz T. Mlynarczyk Dorota Chelminiak-Dudkiewicz Halina Kaczmarek Tomasz Goslinski Marta Ziegler-Borowska 《International journal of molecular sciences》2022,23(14)
In recent years, new cross-linkers from renewable resources have been sought to replace toxic synthetic compounds of this type. One of the most popular synthetic cross-linking agents used for biomedical applications is glutaraldehyde. However, the unreacted cross-linker can be released from the materials and cause cytotoxic effects. In the present work, dialdehyde starch nanocrystals (NDASs) were obtained from this polysaccharide nanocrystal form as an alternative to commonly used cross-linking agents. Then, 5–15% NDASs were used for chemical cross-linking of native chitosan (CS), gelatin (Gel), and a mixture of these two biopolymers (CS-Gel) via Schiff base reaction. The obtained materials, forming thin films, were characterized by ATR-FTIR, SEM, and XRD analysis. Thermal and mechanical properties were determined by TGA analysis and tensile testing. Moreover, all cross-linked biopolymers were also characterized by hydrophilic character, swelling ability, and protein absorption. The toxicity of obtained materials was tested using the Microtox test. Dialdehyde starch nanocrystals appear as a beneficial plant-derived cross-linking agent that allows obtaining cross-linked biopolymer materials with properties desirable for biomedical applications. 相似文献
536.
Joanna Bojarska Martin Breza Milan Remko Malgorzata Czyz Anna Gajos-Michniewicz Micha Zimecki Krzysztof Kaczmarek Izabela D. Madura Jakub M. Wojciechowski Wojciech M. Wolf 《International journal of molecular sciences》2022,23(13)
Short peptides have great potential as safe and effective anticancer drug leads. Herein, the influence of short cyclic peptides containing the Pro-Pro-Phe-Phe sequence on patient-derived melanoma cells was investigated. Cyclic peptides such as cyclo(Leu-Ile-Ile-Leu-Val-Pro-Pro-Phe-Phe-), called CLA, and cyclo(Pro-homoPro-β3homoPhe-Phe-), called P11, exert the cytotoxic and the cytostatic effects in melanoma cells, respectively. CLA was the most active peptide as it reduced the viability of melanoma cells to 50% of control at about 10 µM, whereas P11 at about 40 µM after 48 h incubation. Interestingly, a linear derivative of P11 did not induce any effect in melanoma cells confirming previous studies showing that cyclic peptides exert better biological activity compared to their linear counterparts. According to in silico predictions, cyclic tetrapeptides show a better pharmacokinetic and toxic profile to humans than CLA. Notably, the spatial structure of those peptides containing synthetic amino acids has not been explored yet. In the Cambridge Structural Database, there is only one such cyclic tetrapeptide, cyclo((R)-β2homoPhe-D-Pro-Lys-Phe-), while in the Protein Data Bank—none. Therefore, we report the first crystal structure of cyclo(Pro-Pro-β3homoPhe-Phe-), denoted as 4B8M, a close analog of P11, which is crucial for drug discovery. Comparative molecular and supramolecular analysis of both structures was performed. The DFT findings revealed that 4B8M is well interpreted in the water solution. The results of complex Hirshfeld surface investigations on the cooperativity of interatomic contacts in terms of electrostatic and energetic features are provided. In short, the enrichment ratio revealed O…H/H…O and C…H/H…C as privileged intercontacts in the crystals in relation to basic and large supramolecular H-bonding synthon patterns. Furthermore, the ability of self-assemble 4B8M leading to a nanotubular structure is also discussed. 相似文献
537.
Kamil Wojtkowiak Mariusz Michalczyk Wiktor Zierkiewicz Aneta Jezierska Jarosaw J. Panek 《International journal of molecular sciences》2022,23(22)
It is postulated that the overexpression of Carbonic Anhydrase isozyme IX in some cancers contributes to the acidification of the extracellular matrix. It was proved that this promotes the growth and metastasis of the tumor. These observations have made Carbonic Anhydrase IX an attractive drug target. In the light of the findings and importance of the glycoprotein in the cancer treatment, we have employed quantum–chemical approaches to study non-covalent interactions in the binding pocket. As a ligand, the acetazolamide (AZM) molecule was chosen, being known as a potential inhibitor exhibiting anticancer properties. First-Principles Molecular Dynamics was performed to study the chalcogen and other non-covalent interactions in the AZM ligand and its complexes with amino acids forming the binding site. Based on Density Functional Theory (DFT) and post-Hartree–Fock methods, the metric and electronic structure parameters were described. The Non-Covalent Interaction (NCI) index and Atoms in Molecules (AIM) methods were applied for qualitative/quantitative analyses of the non-covalent interactions. Finally, the AZM–binding pocket interaction energy decomposition was carried out. Chalcogen bonding in the AZM molecule is an important factor stabilizing the preferred conformation. Free energy mapping via metadynamics and Path Integral molecular dynamics confirmed the significance of the chalcogen bond in structuring the conformational flexibility of the systems. The developed models are useful in the design of new inhibitors with desired pharmacological properties. 相似文献
538.
Prashamsa Koirala Sung-Po R. Chen Jennifer C. Boer Zeinab G. Khalil Cyril Deceneux Georgia Goodchild Lantian Lu Mohammad Omer Faruck Ahmed O. Shalash Sahra Bashiri Robert J. Capon Waleed M. Hussein Michael J. Monteiro Magdalena Plebanski Istvan Toth Mariusz Skwarczynski 《Advanced functional materials》2023,33(12):2209304
Antigens incorporated in subunit vaccines are typically poorly immunogenic, so a strong immunostimulant (adjuvant) and/or delivery system is required to boost immunogenicity. In this work, the various functional polymer nanostructures, that is, rods, worms, spheres, and tadpoles are used to develop potent peptide antigen delivery systems. The antigen PADRE-J8 (PJ8), derived from Group A Streptococcus (GAS) M-protein, is either physically mixed or chemically conjugated to polymeric nanoparticles of different shapes. The physical mixture of polymeric nanoparticles and antigen is more effective in inducing antibody production than their chemical conjugates. Moreover, rod-shaped polymeric nanoparticles in physical mixture with PJ8 elicited higher and more opsonic antibody titers than powerful complete Freund's adjuvant (CFA)-adjuvanted antigen. Herein, for the first time it is demonstrated that a) the block copolymer, in nanoparticle form, can act as an immune adjuvant, b) nanoparticle shape plays a crucial role in their immunogenicity, and c) antigen conjugation is not required, nor is antigen encapsulation or absorption. 相似文献
539.
Ethan Rosenberg Jackson Bauer Eunsoo Cho Abinash Kumar Jonathan Pelliciari Connor A Occhialini Shuai Ning Allison Kaczmarek Richard Rosenberg John W. Freeland Yu-Chia Chen Jian-Ping Wang James LeBeau Riccardo Comin F. M. F. de Groot Caroline A Ross 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(30):2300824
Complex oxide films stabilized by epitaxial growth can exhibit large populations of point defects which have important effects on their properties. The site occupancy of pulsed laser-deposited epitaxial terbium iron garnet (TbIG) films with excess terbium (Tb) is analyzed, in which the terbium:iron (Tb:Fe)ratio is 0.86 compared to the stoichiometric value of 0.6. The magnetic properties of the TbIG are sensitive to site occupancy, exhibiting a higher compensation temperature (by 90 K) and a lower Curie temperature (by 40 K) than the bulk Tb3Fe5O12 garnet. Data derived from X-ray core-level spectroscopy, magnetometry, and molecular field coefficient modeling are consistent with occupancy of the dodecahedral sites by Tb3+, the octahedral sites by Fe3+, Tb3+ and vacancies, and the tetrahedral sites by Fe3+ and vacancies. Energy dispersive X-ray spectroscopy in a scanning transmission electron microscope provides direct evidence of TbFe antisites. A small fraction of Fe2+ is present, and oxygen vacancies are inferred to be present to maintain charge neutrality. Variation of the site occupancies provides a path to considerable manipulation of the magnetic properties of epitaxial iron garnet films and other complex oxides, which readily accommodate stoichiometries not found in their bulk counterparts. 相似文献
540.
Pattern Analysis and Applications - The method of the learning of vague languages which represent distorted/ambiguous patterns is proposed in the paper. The goal of the method is to infer the... 相似文献