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51.
Katsuaki Ieguchi Masabumi Funakoshi Taishi Mishima Kohtaro Takizawa Tsutomu Omori Fumio Nakamura Makoto Watanabe Mayumi Tsuji Yuji Kiuchi Shinichi Kobayashi Takuya Tsunoda Yoshiro Maru Satoshi Wada 《International journal of molecular sciences》2022,23(18)
Emerging evidence suggests that neural activity contributes to tumor initiation and its acquisition of metastatic properties. More specifically, it has been reported that the sympathetic nervous system regulates tumor angiogenesis, tumor growth, and metastasis. The function of the sympathetic nervous system in primary tumors has been gradually elucidated. However, its functions in pre-metastatic environments and/or the preparation of metastatic environments far from the primary sites are still unknown. To investigate the role of the sympathetic nervous system in pre-metastatic environments, we performed chemical sympathectomy using 6-OHDA in mice and observed a decrease in lung metastasis by attenuating the recruitment of myeloid-derived suppressor cells. Furthermore, we note that neuro-immune cell interactions could be observed in tumor-bearing mouse lungs in conjunction with the decreased expression of Sema3A. These data indicate that the sympathetic nervous system contributes to the preparation of pre-metastatic microenvironments in the lungs, which are mediated by neuro-immune cell interactions. 相似文献
52.
We studied sea surface temperature (SST) retrieval algorithms for Sendai Bay, using output from the thermal-infrared channels of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on board Terra. While the highest resolutions of other satellite SST products are about 1 km, the ASTER thermal-infrared channels provide 90-m spatial resolution. To develop the ASTER algorithm, we employed statistical methods in which SSTs retrieved from the thermal-infrared measurements were tuned against the Moderate Resolution Imaging Spectroradiometer (MODIS) SST product with a 1-km spatial resolution. Terra also carries a MODIS sensor, which observed the same area as the ASTER sensor at the same time. The MODIS SST was validated around Sendai Bay, revealing a bias of −0.15 °C and root mean-square difference (RMSD) of 0.67 °C against in situ SSTs. Taking into account the spatial-resolution difference between ASTER and MODIS, match-up was generated only if the variability of ASTER brightness temperatures (T13) was small in a pixel of MODIS SST (MP). The T13 within one MP was about 121 pixels. The standard deviation (σ13) of T13 was calculated for each cloud-free MP, and the threshold of σ13 for choosing match-up MPs was decided by analyzing the σ13 histogram of one ASTER image. The 15 synchronous pairs of ASTER/MODIS images are separated into two groups of 8 pairs called set (A) and 7 pairs called set (B). Using the common procedure, the match-ups are generated for set (A) and set (B). The former is used for developing the ASTER Multi-Channel SST (MCSST) algorithm, and the latter for validation of the developed ASTER SST. Analysis of the whole 15 pairs indicated that ASTER SST does not depend on the satellite zenith angle. We concluded that, using Akaike's information criterion with set (A) match-ups, the multiple regression formula with all five thermal-infrared channels was adequate for the ASTER SST retrieval. Validation of ASTER SST using match-up set (B) indicated a bias of 0.101 °C and RMSD of 0.455 °C. 相似文献
53.
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55.
l-Menthyl alpha-D-glucopyranosyl-(1-->4)-alpha-d-glucopyranoside (alpha-MenG2), a novel glycoside of l-menthol, was synthesized enzymatically and its physicochemical properties were characterized. Production of alpha-MenG2 from l-menthyl alpha-d-glucopyranoside (alpha-MenG) was attempted since we had already succeeded in the high-yield production of alpha-MenG using a Xanthomonas campestris enzyme (Nakagawa H., et al. J. Biosci. Bioeng., 89, 138-144, 2000). Through production tests on enzymes, it was confirmed that cyclodextrin glucanotransferase (CGTase) from Bacillus macerans produced l-menthyl alpha-D-maltooligosides (alpha-MenG(n)), containing alpha-MenG2, from alpha-MenG and soluble starch. When 10 ml of a 10 mM citrate-10 mM phosphate buffer (pH 6.0) containing 150 mg of alpha-MenG, 3 g of soluble starch and CGTase was shaken at 70 degrees C for 24 h, a total of 81.8% alpha-MenG was reacted. The molar conversion yields of alpha-MenG2 and alpha-MenG(n) with alpha-glucose degrees of polymerization of 3-18, based on the amount of alpha-MenG supplied, reached 16.1% and 65.7%, respectively. For efficient production of alpha-MenG2, the reaction mixture was treated with alpha-amylase of Aspergillus oryzae, and alpha-MenG(n) were mainly converted into alpha-MenG2: finally, the molar conversion yield of alpha-MenG2 reached 74.2% based on the amount of alpha-MenG supplied. alpha-MenG2 was purified and its molecular structure was confirmed by 13C-NMR, 1H-NMR and two-dimensional HMBC (heteronuclear multiple-bond coherence). alpha-MenG2 and its aqueous solution tasted bitter and a little sweet at first, but in a few minutes, a refreshing flavor and sweetness spread. At 20 degrees C the solubility of alpha-MenG2 in pure water was 29.6 g/100 ml, approximately 1570-fold that of alpha-MenG. 相似文献
56.
Kurosu J Sato T Yoshida K Tsugane T Shimura S Kirimura K Kino K Usami S 《Journal of Bioscience and Bioengineering》2002,93(3):328-330
Alpha-arbutin, a useful cosmetic ingredient, was selectively synthesized by alpha-anomer-selective glucosylation of hydroquinone with maltose as a glucosyl donor using lyophilized cells of Xanthomonas campestris WU-9701 as a biocatalyst. When 45 mM hydroquinone and 120 mg of lyophilized cells showing 11 nkat of alpha-glucosyl transfer activity were shaken in 2 ml of 10 mM H3BO3NaOHKCl buffer (pH 7.5) containing 1.2 M maltose at 40 degrees C, only one form of hydroquinone glucoside was selectively obtained as a product and identified as hydroquinone 1-O-alpha-D-glucopyranoside (alpha-arbutin) by 13C-NMR, 1H-NMR and two-dimensional HMBC analysis. Although hydroquinone has two phenolic -OH groups at the para position in its structure, only one -OH group, but not both -OHs, was glucosylated and no other glucosylated products such as maltotriose were detected in the reaction mixture. The reaction at 40 degrees C for 36 h under optimum conditions yielded 42 mM alpha-arbutin, and the maximum molar conversion yield based on the amount of hydroquinone supplied reached 93%. 相似文献
57.
Yasumoto Tomita Hirotaka Tamura Masaya Kibune Junji Ogawa Kohtaro Gotoh Tadahiro Kuroda 《Solid-State Circuits, IEEE Journal of》2007,42(3):627-636
This paper presents a 20-Gb/s simultaneous bidirectional transceiver using a resistor-transconductor (R-gm) hybrid in standard 0.11-mum CMOS. The R-gm hybrid separates the inbound signal from the signal line voltage and current without using a replica driver. It eliminates the need for precise matching between the replica- and main-driver characteristics, enabling a data rate of 20 Gb/s per differential pair, which is the highest reported for bidirectional signaling. The transceiver occupies 1.02 mm and consumes 260 mW at 20 Gb/s with a bit error rate of less than 10-12. The area and power overhead due to the hybrid are 0.002 mm2 and 7 mW, and correspond to 0.2% and 3% of the total transceiver area and power consumption 相似文献
58.
Kohtaro Tadaki 《Natural computing》2012,11(1):117-128
In 1975 Chaitin introduced his
\Upomega\Upomega number as a concrete example of random real. The real
\Upomega\Upomega is defined based on the set of all halting inputs for an optimal prefix-free machine U, which is a universal decoding algorithm used to define the notion of program-size complexity. Chaitin showed
\Upomega\Upomega to be random by discovering the property that the first n bits of the base-two expansion of
\Upomega\Upomega solve the halting problem of U for all binary inputs of length at most n. In this article, we introduce a new variant
\Uptheta\Uptheta of Chaitin
\Upomega\Upomega number. The real
\Uptheta\Uptheta is defined based on the set of all compressible strings. We investigate the distribution of compressible strings and show
that
\Uptheta\Uptheta is random. In addition, we generalize
\Uptheta\Uptheta to
\Uptheta(Q, R)\Uptheta(Q, R) with reals Q, R > 0 and study its properties. In particular, we show that the computability of the real
\Uptheta(T, 1)\Uptheta(T,\,1) gives a sufficient condition for a real T ∈ (0, 1) to be a fixed point for partial randomness, i.e., to satisfy that the compression rate of T equals to T. 相似文献
59.
Shin-ichi Tadaki 《Computer Physics Communications》2011,(1):237-239
Improvement in time resolution sometimes introduces fast (short-range) random noises into temporal data sequences. These noises affect the results of power-spectrum analyses and the detrended fluctuation analysis (DFA). The DFA is one of useful methods for analyzing long-range correlations in non-stationary sequences. The effects of noises are discussed based on artificial temporal sequences. Short-range noises prevent power-spectrum analyses from detecting long-range correlations. The DFA can extract long-range correlations from noisy time sequences. The DFA also gives the threshold time length, under which the noises dominate. 相似文献
60.
This paper describes a method for recognizing partially occluded objects under different levels of illumination brightness
by using the eigenspace analysis. In our previous work, we developed the “eigenwindow” method to recognize the partially occluded
objects in an assembly task, and demonstrated with sufficient high performance for the industrial use that the method works
successfully for multiple objects with specularity under constant illumination. In this paper, we modify the eigenwindow method
for recognizing objects under different illumination conditions, as is sometimes the case in manufacturing environments, by
using additional color information. In the proposed method, a measured color in the RGB color space is transformed into one
in the HSV color space. Then, the hue of the measured color, which is invariant to change in illumination brightness and direction,
is used for recognizing multiple objects under different illumination conditions. The proposed method was applied to real
images of multiple objects under various illumination conditions, and the objects were recognized and localized successfully. 相似文献