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51.
Ari E Kaya Y Demir H Cebi A Alp HH Bakan E Odabasi D Keskin S 《Hemodialysis international. International Symposium on Home Hemodialysis》2011,15(4):453-459
Oxidative stress is accepted as a nonclassical cardiovascular risk factor in chronic renal failure patients. The aim of this study was to evaluate the relation between oxidative DNA damage (8‐hydroxy‐2′‐deoxyguanosine/deoxyguanosine [8‐OHdG/dG] ratio), oxidative stress biomarkers, antioxidant enzymes, and carotid artery intima‐media thickness (CIMT) in hemodialysis (HD) patients. Forty chronic HD patients without known atherosclerotic disease and 48 age‐ and sex‐matched healthy individuals were included in the study. Plasma malondialdehyde (MDA) levels and 8‐OHdG/dG ratio were determined as oxidative stress markers. Superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were measured as antioxidants. CIMT was assessed by carotid artery ultrasonography. 8‐OHdG/dG ratios and MDA levels were higher; SOD and GPx activities were lower in HD patients compared to controls. HD patients had significantly higher CIMT compared to controls (0.61 ± 0.08 vs. 0.42 ± 0.05, p < 0.001). There was a significant positive correlation between CIMT and 8‐OHdG/dG ratio (r = 0.57, p < 0.01) and MDA levels (r = 0.41, p < 0.01), while there was a significant negative correlation between CIMT and SOD (r = ?0.47, p < 0.01) and GPx levels (r = ?0.62, p < 0.01). It is firstly demonstrated that CIMT is positively correlated with oxidative DNA damage in HD patients without known atherosclerotic disease. 相似文献
52.
Celik A Melek M Yuksel S Onrat E Avsar A 《Hemodialysis international. International Symposium on Home Hemodialysis》2011,15(2):193-199
Patients with end-stage renal disease (ESRD) are likely to have cardiac autonomic dysfunction, which is related with an increased risk of sudden death. The aim of this study is to detect cardiac autonomic dysfunction in patients with ESRD and to evaluate the possible acute effects of hemodialysis (HD) on cardiac autonomic functions measured by heart rate variability (HRV) and heart rate turbulence (HRT). Thirty-one (mean age 50 ± 13 years, 15 males) with ESRD on regular HD program and 31 healthy volunteers (mean age 51 ± 12 years, 15 males) were included in the study. Twenty-four-hour ambulatory electrocardiogram recordings were taken from the subjects before and after HD and from the control group. Heart rate variability and HRT parameters were calculated from these recordings. All of the HRV and HRT parameters were found to be significantly blunted in patients in comparison with healthy individuals. There were significant differences in HRV after HD, but similar differences were not observed in HRT parameters. Cardiac autonomic functions were significantly altered in patients with ESRD. Heart rate turbulence parameters seemed to be less affected from HD and may be more useful in the evaluation of cardiac autonomic functions in the ESRD population. 相似文献
53.
Murat Ates Alpay Garip Ozan Yörük Yuksel Bayrak Ozge Kuzgun Murat Yildirim 《塑料、橡胶和复合材料》2013,42(4):168-184
ABSTRACTSupercapacitor properties of rGO, CuO, PEDOT and rGO/CuO at [rGO]o/[CuO]o?=?1:1; 1:1.5; 1:2 and rGO/CuO/PEDOT nanocomposite at [rGO]o/[CuO]o/[EDOT]o?=?1:1:1; 1:1:3; 1:1:5 were investigated using chemical reduction of GO and in-situ polymerisation process. SEM-EDX, HRTEM, BET surface area analysis confirm the nanocomposite formations. Nanocomposite materials are also analysed through FTIR-ATR, Raman, TGA-DTA, GCD, CV and EIS. The highest specific capacitance of C sp?=?156.7 F/g at 2?mV/s is determined as rGO/CuO/PEDOT at [rGO]o/[CuO]o/[EDOT]o?=?1:1:5. In addition, two-electrode supercapacitor device for rGO/CuO/PEDOT at [rGO]o/[CuO]o/[EDOT]o?=?1:1:5 are found to provide a maximum specific energy (E?=?14.15 Wh/kg at 20?mA) and specific power (P?=?24730 W/kg at 50?mA), electrical serial resistance (ESR?=?13.33 Ω) with good capacity retention after 3000 cycles. An equivalent circuit model of LR1(CR2)(QR3) is proposed to interpret the EIS data. The supercapacitor performance of the rGO/CuO/PEDOT nanocomposite electrode indicates the synergistic effect of hybrid supercapacitors. 相似文献
54.
Sheehan Teige P.; Cirrito John; Numan Marilyn J.; Numan Michael 《Canadian Metallurgical Quarterly》2000,114(2):337
Evidence indicates there is a neural system that inhibits maternal behavior in virgin rats. It has been suggested that pregnancy hormones promote the onset of maternal behavior by reducing the behavioral influence of this system. The authors used c-Fos immunocytochemistry to identify brain regions more activated by pup exposure in nonmaternal rats than in maternal rats. Previous experiments indicated that some of these regions, such as the posterodorsal medial amygdala and several medial hypothalamic sites, inhibit maternal behavior. For others, such as the ventral lateral septum, dorsal premammillary nucleus, and principal bed nucleus of the stria terminalis, this is the first indication that they could also inhibit maternal responding. These regions have previously been implicated in promoting defensive behaviors, consistent with the finding that nonmaternal rats actively avoid pups. These findings suggest the existence of a neural circuit through which pup exposure could promote defensive responses in virgin rats, and how pregnancy hormones could reduce such activity to stimulate maternal behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
Impacts of Climate Change on Water Resources Availability and Agricultural Water Demand in the West Bank 总被引:3,自引:1,他引:2
Numan Mizyed 《Water Resources Management》2009,23(10):2015-2029
Global climate change is predicted as a result of increased concentrations of greenhouse gasses in the atmosphere. It is predicted
that climate change will result in increasing temperature by 2 to 6°C and a possible reduction of precipitation of up to 16%
in the Mediterranean basin. In this study, the West Bank is taken as a case study from the Mediterranean basin to evaluate
the effects of such climate change on water resources availability and agricultural water demands. Due to the uncertainty
in climate change impacts on temperature and precipitation, a number of scenarios for these impacts were assumed within the
range of predicted changes. For temperature, three scenarios of 2, 4 and 6°C increase were assumed. For precipitation, two
scenarios of no change and 16% precipitation reduction were assumed. Based on these scenarios, monthly evapotranspiration
and monthly precipitation excess depths were estimated at seven weather stations distributed over the different climatic and
geographical areas of the West Bank. GIS spatial analyses showed that the increase in temperature predicted by climate change
could potentially increase agricultural water demands by up to 17% and could also result in reducing annual groundwater recharge
by up to 21% of existing values. However, the effects of reduced precipitation resulting from climate change are more enormous
as a 16% reduction in precipitation could result in reducing annual groundwater recharge in the West Bank by about 30% of
existing value. When this effect is combined with a 6°C increase in temperature, the reduction in groundwater recharge could
reach 50%. 相似文献
56.
Waqas Ahmad Wattoo Donghan Feng Muhammad Yousif Sohaib Tahir Muhammad Tuoqeer Anwar Muhammad Numan 《国际能源研究杂志》2019,43(10):5447-5459
Demand response is considered to be a realistic and comparatively inexpensive solution aimed at increasing the penetration of renewable generations into the bulk electricity systems. The work in this paper highlights the demand response in conjunction with the optimal capacity of installed wind energy resources allocation. Authors proposed a total annual system cost model to minimize the cost of allocating wind power generating assets. This model contains capacity expansion, production, uncertainty, wind variability, emissions, and elasticity in demand to find out cost per hour to deliver electricity. A large‐scale electric grid (25 GW) is used to apply this model. Authors discovered that demand response based on interhourly system is not as much helpful as demand response grounded on intrahourly system. According to results, 32% wind generation share will provide the least cost. It is also worth noting that optimal amount of wind generation is much sensitive to installation cost as well as carbon tax. 相似文献
57.
Cooper Patricia V.; Numan Bobbi K.; Crosson Bruce; Velozo Craig A. 《Canadian Metallurgical Quarterly》1989,3(1):1
Memory components of story and list recall were derived for 48 head-injured patients (mean age 33.5 yrs) using regression techniques. Ss completed such measures as the Wechsler Memory Scale. General and verbal memory components, respectively, contributed the most variance to both story and list recall under both immediate and delayed conditions. Although they share substantial variance, list and story recall were not identical. Willingness to repeat oneself contributed to all types of recall, except delayed story recall. It was hypothesized that long-term storage contributed to immediate list recall ability, active semantic organization contributed to delayed list recall ability, and attentional fluctuations contributed to delayed story recall ability. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
In Exp I, with 21 female Charles River CD rats, bilateral electrolytic lesions of the ventral tegmental area (VTA) severely disrupted maternal behavior. In Exp II, with 56 Ss, lactating Ss that received a unilateral knife cut severing the lateral connections of the medial preoptic area (MPOA) paired with a contralateral lesion of the VTA showed more severe maternal behavior deficits than Ss that received (a) a cut severing the lateral connections of the MPOA paired with an ipsilateral VTA lesion; (b) a cut severing the lateral connections of the MPOA paired with a contralateral lesion of the medial hypothalamus posterior to the MPOA; or (c) a cut severing the lateral connections of the lateral preoptic area paired with a contralateral VTA lesion. The oral components of maternal behavior (retrieving and nest building) were particularly affected as a result of bilateral damage to the system extending from the preoptic area to the VTA. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
Gill Waqas Amin Ali Dima An Boo Hyun Syed Wajih U. Saeed Numan Al-shaibah Muneera Elfadel Ibrahim M. Al Dahmani Sultan Choi Daniel S. 《Microsystem Technologies》2020,26(8):2527-2533
Microsystem Technologies - This paper presents the design of a novel multi-ring vibratory gyroscope. The design incorporates two sets of rings, inner and outer, separated by a set of perforated... 相似文献
60.
Comparison of the performance of copper oxide and yttrium oxide nanoparticle based hydroxylethyl cellulose electrolytes for supercapacitors 下载免费PDF全文
Biodegradable solid polymer electrolyte (SPE) systems composed of hydroxylethyl cellulose blended with copper(II) oxide (CuO) and yttrium(III) oxide (Y2O3) nanoparticles as fillers, magnesium trifluoromethane sulfonate salt, and 1‐ethyl‐3‐methylimidazolium trifluoromethane sulfonate ionic liquid were prepared, and the effects of the incorporation of CuO and Y2O3 nanoparticles on the performance of the SPEs for electric double‐layer capacitors (EDLCs) were compared. The X‐ray diffraction results reveal that the crystallinity of the SPE complex decreased upon inclusion of the Y2O3 nanoparticles compared to CuO nanoparticles; this led to a higher ionic conductivity of the Y2O3‐based SPE [(3.08 ± 0.01) × 10?4 S/cm] as compared to CuO [(2.03 ± 0.01) × 10?4 S/cm]. The EDLC performances demonstrated that the cell based on CuO nanoparticles had superior performance in terms of the specific capacitance, energy, and power density compared to the Y2O3‐nanoparticle‐based cell. However, Y2O3‐nanoparticle‐based cell displayed a high cyclic retention (91.32%) compared to the CuO‐nanoparticle‐based cell (80.46%) after 3000 charge–discharge cycles. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44636. 相似文献