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1.
Akira Minami Yuuki Kurebayashi Tadanobu Takahashi Tadamune Otsubo Kiyoshi Ikeda Takashi Suzuki 《International journal of molecular sciences》2021,22(6)
Sialidase cleaves sialic acid residues from glycans such as glycoproteins and glycolipids. In the brain, desorption of the sialic acid by sialidase is essential for synaptic plasticity, learning and memory and synaptic transmission. BTP3-Neu5Ac has been developed for sensitive imaging of sialidase enzyme activity in mammalian tissues. Sialidase activity in the rat hippocampus detected with BTP3-Neu5Ac increases rapidly by neuronal depolarization. It is presumed that an increased sialidase activity in conjunction with neural excitation is involved in the formation of the neural circuit for memory. Since sialidase inhibits the exocytosis of the excitatory neurotransmitter glutamate, the increased sialidase activity by neural excitation might play a role in the negative feedback mechanism against the glutamate release. Mammalian tissues other than the brain have also been stained with BTP3-Neu5Ac. On the basis of information on the sialidase activity imaging in the pancreas, it was found that sialidase inhibitor can be used as an anti-diabetic drug that can avoid hypoglycemia, a serious side effect of insulin secretagogues. In this review, we discuss the role of sialidase in the brain as well as in the pancreas and skin, as revealed by using a sialidase activity imaging probe. We also present the detection of influenza virus with BTP3-Neu5Ac and modification of BTP3-Neu5Ac. 相似文献
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A method for estimating the sway angle using an observer has already been proposed. The state observer estimates the sway angle accurately and must use the detected sway angle value. However, the estimated sway angle has an error owing to rope length error, friction force, and wind. Moreover, the container mass cannot be determined, and therefore the observer parameter is not suitable. We already proposed robust antisway control for overcoming rope length error without adding a new sensor. Further, we designed a friction disturbance observer to cancel out the influence of the friction force. In this paper, we first propose a container mass estimation method when a crane system performs rolling up control. The observer parameter can be selected using the estimated mass value. Second, in crane parallel shift control, we propose a robust antisway control even when there is a wind disturbance. We design a wind disturbance observer and propose a wind disturbance estimator to separate the friction observer output from the wind disturbance observer output. We confirm through experiments that the proposed method can reduce vibration. 相似文献
4.
Kento Ishii Chika Matsunaga Kiyoshi Kobayashi Adam J. Stevenson Caroline Tardivat Tetsuo Uchikoshi 《Journal of the European Ceramic Society》2021,41(4):2709-2715
The Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF)-based multi-layered oxygen separation membrane was fabricated by the sequential electrophoretic deposition (EPD) process. A thin porous/dense bi-layer of BSCF was formed on a thick porous support of BSCF. The porous support prepared by a sacrificial template method using BSCF powder mixed with wheat starch (30 wt%) as a pore-forming agent, followed by uniaxial pressing and low-temperature sintering, was directly used as an EPD electrode. A thin BSCF layer was first formed on the porous support, and then a thin BSCF + PMMA (polymethyl methacrylate) layer was sequentially formed on the thin BSCF layer using a bimodal suspension of BSCF and PMMA. A 30-μm thin porous/dense bi-layer of BSCF of which the total thickness was obtained by optimizing the processes of EPD and subsequent co-sintering. The oxygen separation performance of 3.7 ml (STP) min?1 cm?2 at 860 °C was achieved for the BSCF-based multi-layered oxygen separation membrane. 相似文献
5.
Shunzo Kawajiri Takayuki Kawaguchi Yasuharu Watanabe Hiroshi Hayakawa Yasunori Miyamori Dai Nakamura Satoshi Yamashita 《Soils and Foundations》2019,59(3):764-782
For one week from August 17 to 23, 2016, three consecutive typhoons made landfall in Hokkaido for the first time on record. These typhoons and the front they stimulated brought record-breaking torrential rain over the eastern part of Hokkaido. To investigate the damage to grounds and rivers resulting from this rainfall, the Japan Society of Civil Engineers (JSCE) and the Japanese Geotechnical Society (JGS) formed a disaster research group to conduct an investigation. This report provides the results of the investigation into damage to the grounds of areas along the Tokoro River of the Okhotsk region, Hokkaido, that suffered from this tremendous and diverse disaster. Specifically, the report describes the situation of the levees which were broken and eroded by the overflowing water, the shape of the levee bodies, the levee body soil properties examined by observation of the sections, as well as the occurrence of sand boiling and air blows. The washout of road embankments as well as damage to road bridge mounting fills and abutment backfills were also investigated. The investigation has demonstrated the need to clarify the resistance of the abutment backfills and levee bodies to flowing water as well as the geotechnical predominant factors in order to clarify the mechanisms behind erosion and washout, the need to review new measures that allow for the scale of sand boiling and resultant changes in levee body stability, and the fact that the existing embankments were able to temporarily suppress the flooding water which had spilled over from the river. Furthermore, although it has been identified that the findings of a study on an embankment washout associated with a tsunami can be applied to measures taken against the overflowing water, it has also been found necessary to clarify the predominant geotechnical factors using model tests and to use a more sophisticated analytical approach to establish a geotechnical stability review as soon as possible in order to prevent the levees and embankments from being eroded and washed out due to overflowing water. 相似文献
6.
Alexandru I. Petrisor Sandra Szyjka Tomohiro Kawaguchi Pieter T. Visscher Robert Sean Norman Alan W. Decho 《International journal of molecular sciences》2014,15(1):850-877
Microspatial arrangements of sulfate-reducing microorganisms (SRM) in surface microbial mats (~1.5 mm) forming open marine stromatolites were investigated. Previous research revealed three different mat types associated with these stromatolites, each with a unique petrographic signature. Here we focused on comparing “non-lithifying” (Type-1) and “lithifying” (Type-2) mats. Our results revealed three major trends: (1) Molecular typing using the dsrA probe revealed a shift in the SRM community composition between Type-1 and Type-2 mats. Fluorescence in-situ hybridization (FISH) coupled to confocal scanning-laser microscopy (CSLM)-based image analyses, and 35SO4
2−-silver foil patterns showed that SRM were present in surfaces of both mat types, but in significantly (p < 0.05) higher abundances in Type-2 mats. Over 85% of SRM cells in the top 0.5 mm of Type-2 mats were contained in a dense 130 μm thick horizontal layer comprised of clusters of varying sizes; (2) Microspatial mapping revealed that locations of SRM and CaCO3 precipitation were significantly correlated (p < 0.05); (3) Extracts from Type-2 mats contained acylhomoserine-lactones (C4-, C6-, oxo-C6 C7-, C8-, C10-, C12-, C14-AHLs) involved in cell-cell communication. Similar AHLs were produced by SRM mat-isolates. These trends suggest that development of a microspatially-organized SRM community is closely-associated with the hallmark transition of stromatolite surface mats from a non-lithifying to a lithifying state. 相似文献
7.
You Zhou Tatsuki Ohji Hideki Hyuga Yu‐ichi Yoshizawa Norimitsu Murayama Kiyoshi Hirao 《International Journal of Applied Ceramic Technology》2014,11(5):872-882
Silicon nitride ceramics were prepared from a high‐purity silicon powder doped with 2 mol% Y2O3 and 5 mol% MgO as sintering additives via a route of sintering of reaction‐bonded silicon nitride (SRBSN). The materials sintered at 1900°C for 3, 6, 12, and 24 h had thermal conductivities of 109, 125, 146, and 154 W/m/K, and four‐point bending strengths of 786, 676, 608, and 505 MPa, respectively. The fracture toughness values, determined by the single‐edge‐precracked‐beam (SEPB) method, were 8.4, 8.6, 9.7, and 10.7 MPa m1/2 for the materials sintered for 3, 6, 12, and 24 h, respectively, which were similar to the results measured by the chevron‐notched‐beam (CNB) test method. The materials sintered for longer times (12 and 24 h) showed stronger R‐curve behaviors over longer range of crack extension, in comparison with the materials sintered for shorter times (3 and 6 h). 相似文献
8.
Humic acid, which is a typical microbially refractory organic substance, was extracted from a landfill leachate. The humic acid solution (COD = 367 mg 1−1; TOC = 293 mg 1−1; BOD = 27 mg 1−1) was applied to a batch scale activated sludge treatment after the modification of its biodegradability by γ-ray irradiation. The BOD increased to 64 mg 1−1 by irradiation of 15 kGy (1.5 Mrad), while the COD and TOC decreased to 231 and 230 mg 1−1, respectively. When the irradiated sample was treated with an activated sludge, the BOD decreased rapidly in 2–3 h to about 15 mg 1−1 which was a similar value as the unirradiated sample was treated. The elimination efficiency of TOC by the sludge treatment was approximately equal to that obtained by irradiation of 15 kGy. These facts suggest a utility of applying microbial processes after radiation treatment of microbially refractory wastewaters. 相似文献
9.
Research and Development of the Coprecipitation Process for Lanthanum Germanate Oxyapatite 下载免费PDF全文
Kiyoshi Kobayashi Shouta Kitajima Yukihito Igarashi Tohru Higuchi Yoshio Sakka 《Journal of the American Ceramic Society》2015,98(1):66-70
Although lanthanum germanate oxyapatite (La–Ge–O) has shown good potential for use as a solid electrolyte in energy storage applications, its synthesis has been challenging by either solid‐ or solution‐state methods. In this study, a new synthesis of La–Ge–O was developed through a coprecipitation technique, in which a highly concentrated homogeneous aqueous solution of La and Ge was prepared from aqueous ammonium germanate and lanthanum nitrate solutions with the addition of dilute nitric acid. Several precipitates were formed by pH manipulation, including an amorphous material obtained at pH > 3. Compared to the individual precipitation behaviors of the parent compounds, the amorphous precipitate was formed only from the aqueous two‐component mixture, and appeared to contain both metals. This material was transformed into crystalline mixtures upon heating at 1273 K. The crystalline phases were La2Ge3O9 and hexagonal‐type GeO2 when the precipitate was formed below pH 8, and the La–Ge–O and La2Ge2O7 phases when the precipitate was formed around pH 8. Product formation from the coprecipitate was discussed based on X‐ray diffraction and thermal analyses. The improved availability of La–Ge–O will allow more extensive investigations of its useful properties. 相似文献
10.