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81.
The early vascular plants in the genus Selaginella, which is the sole genus of the Selaginellaceae family, have an important place in evolutionary history, along with ferns, as such plants are valuable resources for deciphering plant evolution. In this study, we sequenced and assembled the plastid genome (plastome) sequences of two Selaginella tamariscina individuals, as well as Selaginella stauntoniana and Selaginella involvens. Unlike the inverted repeat (IR) structures typically found in plant plastomes, Selaginella species had direct repeat (DR) structures, which were confirmed by Oxford Nanopore long-read sequence assembly. Comparative analyses of 19 lycophytes, including two Huperzia and one Isoetes species, revealed unique phylogenetic relationships between Selaginella species and related lycophytes, reflected by structural rearrangements involving two rounds of large inversions that resulted in dynamic changes between IR and DR blocks in the plastome sequence. Furthermore, we present other uncommon characteristics, including a small genome size, drastic reductions in gene and intron numbers, a high GC content, and extensive RNA editing. Although the 16 Selaginella species examined may not fully represent the genus, our findings suggest that Selaginella plastomes have undergone unique evolutionary events yielding genomic features unparalleled in other lycophytes, ferns, or seed plants.  相似文献   
82.
Development of fine grain 316L with small amount of TiC for high radiation-tolerant performance was tried considering the fabrication process of thermo-mechanical treatments. The materials obtained are UFG316L+2.0 mass% TiC with the grain size of 90–270 nm, depending on the final annealing temperature from 700 ℃ to 900 ℃. The materials were examined by transmission electron microscopy observation, X-ray absorption near-edge structure spectroscopy, high voltage electron microscope electron irradiation and stress corrosion cracking by crevice bent beam method in high-temperature water with 8 ppm dissolved oxygen. The test results showed that the material is generally of excellent quality. Especially void swelling induced by the electron irradiation at 400 ℃ is less than 1/10 compared to the commercial SUS316L.  相似文献   
83.
Hesperidin (previously called vitamin P) is a predominant flavanone present in citrus fruits, and is presumed to have a role in their beneficial effect for human health because it possesses various physiological activities. In this study, we investigated the anti-allergic and anti-inflammatory effects of hesperidin and α-glucopyranosyl (αG)-hesperidin, its derivative with enhanced water-solubility, in NC/Nga mice, a human-like mouse model of atopic dermatitis. NC/Nga mice were fed a 0.1% αG-hesperidin or hesperidin diet for 8 weeks. αG-hesperidin and hesperidin feeding effectively inhibited skin lesions and immunoglobulin E (IgE) elevation. At the end of the 8-week-experimental period, the production of inflammatory cytokine interleukin (IL)-17 and interferon-gamma (IFN-γ) from splenocytes was lower in the αG-hesperidin/hesperidin-fed group than in the control group. Changes in mRNA expression in splenocytes are also examined using DNA microarray and real-time RT-PCR. It was revealed that cytotoxic T-lymphocyte antigen 4 (CTLA4), a regulatory T-cell (Treg) marker, was markedly upregulated in splenocytes, particularly by αG-hesperidin feeding. These results suggest that αG-hesperidin attenuated exacerbation of AD-like symptoms, decreased systemic immune hyper-responsiveness in part through the reduction of IgE, IL-17 and IFN-γ, and also modulated Th17/Treg balance in NC/Nga mice. Therefore, αG-hesperidin may be useful in the management of Th17-mediated allergic disorders.  相似文献   
84.
The infrared photoinduced alignment change of liquid‐crystal domains was investigated for a hexagonal columnar mesophase of a liquid‐crystalline triphenylene derivative. A uniform and anisotropic alignment change of domains was observed when a polarized infrared (IR) light corresponding to the wavelength of the aromatic C–C stretching absorption band of the triphenylene core was used to irradiate the sample. The relationship between the aligned azimuthal angle of the columnar axis and the polarization of the IR incident irradiation was investigated. IR absorption dichroism is induced as a result of the reorientation of triphenylene core. Texture observation and polarizing microscope FTIR spectra show that a change of the molecular alignment occurred and that the direction of columns depends on the polarization angle of the IR light used for irradiation. The mechanism of the alignment change in a columnar liquid crystal film by IR irradiation is also discussed. The technique could provide a novel technology to control the columnar alignment of highly viscous liquid crystals.  相似文献   
85.
A series of N-alkyl-N-(heteroaryl-substituted benzyl)-N'-arylurea and related derivatives represented by 2 and 3 have been prepared and evaluated for their ability to inhibit acyl-CoA:cholesterol O-acyltransferase in vitro and to lower plasma cholesterol levels in cholesterol-fed rats in vivo. Among these novel compounds, the type 3 series was superior. A pyrazol-3-yl group on the N-benzyl group of this trisubstituted urea (i.e. 3, Ar1 = pyrazol-3-yl) was identified as a heteroaromatic ring providing a good profile of biological activity. As a result of optimization of the combination with the N-alkyl group (R) and N-aryl group (Ar3), compound 3aq (FR186054) was identified as a new, orally efficacious ACAT inhibitor, which exhibited potent in vitro ACAT inhibitory activity (rabbit intestinal microsomes IC50 = 99 nM) and excellent hypocholesterolemic effects in cholesterol-fed rats, irrespective of administration mode (ED50 = 0.046 mg/kg dosed via the diet, ED50 = 0. 44 mg/kg administered by gavage in PEG400 vehicle). Moreover, a toxicological study revealed compound 3aq to be nontoxic to the adrenal glands of dogs when tested at a single dose of 10 mg/kg po.  相似文献   
86.
87.
The Klason method–dissolution of carbohydrates in sulfuric acid–has been widely used for the determination of lignin content in woody materials. It was an unsolved problem, however, whether Klason lignin still contains carbohydrates. We observed previously that Klason lignin becomes almost completely soluble in water after ozone treatment. In this work, the residual sugar content of Klason lignin was determined on the basis of the above observation.

Water-soluble lignin was prepared by ozone treatment (25 and 45 min) of finely-crushed Klason lignin obtained from spruce and birch wood meals. After hydrolysis with 2N-trifluoroacetic acid followed by sodium borohydride reduction, residual sugars were determined by GLC as their alditol acetates.

Klason lignin ozonated for 25 min contained 0.75% and 0.95% neutral sugars for spruce and birch, respectively. Most of the residual sugars were derived from hemicelluloses. Because ozone degrades carbohydrates, the prolonged ozonation was found to decrease the content of residual sugars. Therefore, the values obtained here are the minimum ones for the residual sugar content in Klason lignin.  相似文献   
88.
The block cipher ARIA has been threatened by side‐channel analysis, and much research on countermeasures of this attack has also been produced. However, studies on countermeasures of ARIA are focused on software implementation, and there are no reports about hardware designs and their performance evaluation. Therefore, this article presents an advanced masking algorithm which is strong against second‐order differential power analysis (SODPA) and implements a secure ARIA hardware. As there is no comparable report, the proposed masking algorithm used in our hardware module is evaluated using a comparison result of software implementations. Furthermore, we implement the proposed algorithm in three types of hardware architectures and compare them. The smallest module is 10,740 gates in size and consumes an average of 47.47 μW in power consumption. Finally, we make ASIC chips with the proposed design, and then perform security verification. As a result, the proposed module is small, energy efficient, and secure against SODPA.  相似文献   
89.
Glaucoma is an optic neuropathy in which the degeneration of retinal ganglion cells (RGCs) results in irreversible vison loss. Therefore, neuroprotection of RGCs from glaucomatous afflictions is crucial for glaucoma treatment. In this study, we aimed to investigate the beneficial effects of statins in the protection of RGCs using a rat model. Glaucomatous injury was induced in rats by chronic ocular hypertension (OHT) achieved after performing a circumlimbal suture. The rats were given either statins such as simvastatin and atorvastatin or a solvent weekly for 6 weeks. Retina sections underwent hematoxylin and eosin, Brn3a, or cleaved casepase-3 staining to evaluate RGC survival. In addition, modulation of glial activation was assessed. While the retinas without statin treatment exhibited increased RGC death due to chronic OHT, statins promoted the survival of RGCs and reduced apoptosis. Statins also suppressed chronic OHT-mediated glial activation in the retina. Our results demonstrate that statins exert neuroprotective effects in rat retinas exposed to chronic OHT, which may support the prospect of statins being a glaucoma treatment.  相似文献   
90.
The optical properties of liquid xenon (LXe) in the vacuum ultra violet (VUV), determining the performance of a scintillation calorimeter, are discussed in detail. The available data, measured in a wider spectral region from visible to UV light, and in a large range of Xe densities, from gas to liquid, are examined. It is shown that this information can be used for deriving the LXe optical properties in the VUV. A comparison is made with the few direct measurements in LXe for VUV light resulting from the LXe excitation by ionizing particles. A useful relation is obtained which connects the Rayleigh scattering length to the refractive index in LXe.  相似文献   
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