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51.
52.
Long-lived proteins can undergo non-enzymatic glycation to form highly crosslinked structures with characteristic fluorescence during aging and diabetes processes. In this paper, a typical fluorophore, named Maillard reaction product X (MRX), was isolated from the hydrolysate of glycated proteins. MRX could be formed by incubation of bovine serum albumin with glucose, followed by acid hydrolysis. The structure of MRX was determined to be 8-hydroxy-5-methyldihydrothiazolo[3,2-alpha] pyridinium-3-carboxylate. MRX was also found to be formed by the incubation of cysteine and arginine with glucose, followed by hydrolysis. We found the formation of MRX in the recently developed genetically diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats and compared them with that in the control Long-Evans Tokushima Otsuka (LETO) rats. Significantly higher levels of MRX were observed from the serum (p < 0.005) and urinary protein (p < 0.001) of OLETF rats in comparison with those of LETO rats. MRX must be a potential candidate as a biomarker for hyperglycemia.  相似文献   
53.
Polydimethylsiloxane (PDMS)–polyamide multiblock copolymers were synthesized by three different methods, i.e., two-step low-temperature solution polycondensation, one-step solution polycondensation, and interfacial polycondensation. In the two-step method, α,ω-diacid chlorideterminated polyamide oligomers were prepared from trans-2,5-dimethylpiperazine (DMP) and terepthaloyl chloride (TPC) or isophthaloyl chloride (IPC) in chloroform in the presence of triethylamine, which in turn were subjected to reaction with α,ω-bis (3-aminopropyl) polydimethylsiloxane (PDMS–diamine) in the same solvent to from multiblock copolymers. In the one-step method, the reaction components, DMP, TPC (or IPC), and PDMS–diamine, were reacted altogether in chloroform in the presence of triethylamine. In the interfacial method, the reaction components were also reacted altogether in an aqueous sodium hydroxide–chloroform two-phase system. These polycondensations afforded the multiblock copolymers having inherent viscosities of 0.1–1.3 dL g?1 in m-cresol. The PDMS–polyamide multiblock copolymers dissolved in formic acid and 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP), and transparent, ductile, and elastomeric films were obtained by casting from the HFIP solutions. The films of the multiblock copolymers prepared by three different methods exhibited similar properties by means of thermal analysis and tensile measurements. In the multiblock copolymers, the tensile strength and modulus of the films decreased with increasing the PDMS content, whereas the elongation at break increased.  相似文献   
54.
A parallel signal processor architecture has been developed for real time motion picture encoding. The architecture is based on spatial parallelism utilization in a picture signal. Plural element processors handle subregional pictures simultaneously without communicating with other element processors. However, due to an overlapsave technique where every sub-picture input area is chosen to be wider than the output area, element processors can carry out continuous processing over an entire picture. In order to increase motion picture processing efficiency as well as system implementation simplicity, a specific element processor LSI chip, composed of a pipeline arithmetic unit, two dimensional address generators, a raster scan signal handler, and a sequence controller, has been developed by using more than 220,000 transistors. The developed parallel processor is shown to be applicable to a software programmable low bit rate TV codec.  相似文献   
55.
A window structure has been applied, for the first time, to the individually addressable monolithic array of GaAlAs high-power lasers. A 100-μm spaced array of four window diffusion stripe lasers with a long-cavity of 600 μm has been fabricated by controllable open-tube two-step diffusion and single-step metalorganic chemical vapor deposition. The window structure and the p-type active stripes with a sufficiently narrow width around 2 μm are formed by diffusion of zinc, which just passes through an n-type active layer. CW output power up to 120 mW without catastrophic damage and a threshold current around 30 mA have been achieved for each element in the wavelength range of 830 nm. Excellent uniformity of device characteristics across an array chip is confirmed. Thermal crosstalk of the elements operating simultaneously is investigated  相似文献   
56.
We have investigated a nonlinear phenomenon which appears in a focused sound in superfluid4He under pressure higher than 18 atm. Wave front distortion of the focused ultrasound by nonlinear effect was obtained by the Fourier transform of the transducer output as a function of the defocusing length. The wave was found to suffer discontinuous wave front distortion for the input power above a certain value. This distortion is well represented by the picture that a second wave whose phase is shifted by approx. develops, and interferes with the original wave. The amplitude of this second wave decreases suddenly as the pressure is lowered below 18 atm and the nonlinear wave front distortion also disappears. The possible mechanism of this second wave generation are discussed.  相似文献   
57.
By employing carefully tailored tert‐butyl alcohol (TBA)‐based freeze‐casting parameters, a large amount of porosity (>70 vol%) and one or two‐dimensional pore channels created were produced into alkali niobate‐based (NKN) ceramics. The relationship between processing factors and microstructures has here been studied, in terms of (i) porosities controlled by adjusting the solid loading in the initial slurry and (ii) strategically attempted freezing direction to make varied pore channels, in which two freezing directions from the bottom or side of mold can produce unidirectional elongated and radially centrosymmetric microstructures, respectively. In addition to that, NKN/epoxy composites with 3‐1 or 3‐2 type polymer channels in the NKN matrix have been fabricated by infiltration of the polymer into the porous NKN hosts. The effect of the channel directions on the mechanical and piezoelectric properties of the composites was investigated for varied volume fractions of the active ceramic phase, mechanical loading, and the poling direction, leading to very high‐piezoelectric g33 coefficients at >60 mV·m/N in the composites with unique channel structures.  相似文献   
58.
A new extractant biuret(C8) is synthesized and tested for solvent extraction of hard acid metals, for example, actinides, and soft acid metals. This compound has a central frame similar to that of malonamide but with an additional amino functional group introduced into the central framework; in this case, both the amidic oxygen atoms and the amino nitrogen atom may bond with metals. We found that both hard and soft acid metals can be extracted from nitric or perchloric acids to n-dodecane using biuret(C8). It is clear that D(Pd, Pu, U) values of approximately 100 can be obtained using 0.1 M biuret(C8)/n-dodecane.  相似文献   
59.
A rapid growth of mixed-signal integrated circuits is driving the needs of multifunction and miniaturization of the component in electronics applications. Polymer-ceramic composites have been of great interest as embedded capacitor materials because they enabled companies to combine the processability of polymers with the high dielectric constant of ceramics. This paper presents the preparations and performance characterizations of novel polymer-ceramic nanocomposites based on new concepts for embedded capacitor application. First, metal particle nickel-filled nanocomposite with high dielectric constant was evaluated as a candidate for embedded capacitors. Two types of nickel particles were selected with the size of 400 and 150nm, respectively. With proper filler loading and highly dispersed, a high dielectric constant of over 90 was observed with a filler loading ratio of 60-vol%. Second, the surface modification of a barium titanate (BTO) particle was also attempted in nanocomposite. Phthalocyanine-coated BTO (Pc-coated BTO) was selected as filler to prepare the composite. Its dielectric constant was observed as over 80 at 1MHz, which was much higher than that of composite derived from commercial BTO. Last, in order to improve the processability of the nanocomposite, 4, 4'-diphenylmethane bismaleimide (BMI) was selected as a matrix polymer by the combination with polyamide (PA). Higher dielectric constant nanocomposite derived from PA/BMI and Pc-coat BTO was obtained, and its potential application towards embedded capacitors was also evaluated.  相似文献   
60.
As a novel partial substitution and surface modification process, we focused on a step-by-step (double-step) supersonic-wave treatment in a Zn-containing aqueous solution without any heat-treatments, and performed the treatment on LiMn2O4 powder. From XRD measurements, it was demonstrated that the lattice constant of LiMn2O4 decreased slightly by the treatments, indicating a partial substitution of Zn for Mn. It was also suggested by SEM–EDX and XPS that Zn was well dispersed in/on the samples and their surfaces were modified by Zn compounds. Such a partial substitution and surface modification was supported by crystal structure analysis based on the Rietveld method using neutron diffraction. Cycle performance of LiMn2O4 was significantly improved by the step-by-step supersonic-wave treatments. In the processes, it was especially effective for the improvement to apply lower and higher frequencies at the first and second steps, respectively, keeping the power higher. The cathode property improvement was considered due to the partial substitution and the surface coating caused by the step-by-step supersonic-wave treatments. From the investigation on the cathodes and electrolytes after the cycle tests, it was suggested that the crystal structure of LiMn2O4 was stabilized by the treatments.  相似文献   
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