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1.
The purposes of this study are to provide an estimation of the incidence of transport injuries in a defined local community in Nicaragua by using the capture-recapture method, and to compare results using this method when data at different levels of severity are utilized.Two sources of injury data were used to monitor injuries: hospital data (inpatient and outpatient) and traffic police records. Characteristics available for matching included name, age, sex, and date of occurrence. The methodology of capture-recapture was used to estimate the ascertainment degree of both sources of data and the estimate mortality and incidence rates. Estimates were calculated both when all hospital data were taken into account (inpatient and outpatient combined) and when only inpatient records were matched against police records.First, including police records and all hospital data, the mortality and morbidity estimates were 35.5/100000 and 43.7/1000 per year, respectively. Second, when outpatients were excluded from the analysis, the corresponding estimates were 28.6/100000 and 7.5/1000, respectively. In non-fatal cases, the ascertainment-corrected coverage through police records was 2.6% and through hospital surveillance 19.0% when both inpatients and outpatients were included. In fatal cases, the corresponding rates were 56.1 and 22.8%, respectively. The combined data set pointed out pedestrians and cyclists as the main risk groups. Most fatalities were due to head injuries.Our results show that neither police records nor hospital records nor the aggregate database provided acceptable coverage of transport-related injuries. Combining police and hospital data by means of capture-recapture analysis produces more valid estimates, but caution must be given to the issue of severity heterogeneity between the two sources.  相似文献   
2.
Recent studies have reported that full monolayers of L-α-dilaurylphosphatidylcholine (L-DLPC) and D-α-dipalmitoylphosphatidylcholine (D-DPPC) formed at interfaces between thermotropic liquid crystals (LCs) and aqueous phases lead to homeotropic (perpendicular) orientations of nematic LCs and that specific binding of proteins to these interfaces (such as phospholipase A 2 binding to D-DPPC) can trigger orientational ordering transitions in the liquid crystals. We report on the nonspecific interactions of proteins with aqueous-LC interfaces decorated with partial monolayer coverage of L-DLPC. Whereas nonspecific interactions of four proteins (cytochrome c, bovine serum albumin, immunoglobulins, and neutravidin) do not perturb the ordering of the LC when a full monolayer of L-DLPC is assembled at the aqueous-LC interface, we observe patterned orientational transitions in the LC that reflect penetration of proteins into the interface of the LC with partial monolayer coverage of L-DLPC. The spatial patterns formed by the proteins and lipids at the interface are surprisingly complex, and in some cases the protein domains are found to compartmentalize lipid within the interfaces. These results suggest that phospholipid-decorated interfaces between thermotropic liquid crystals and aqueous phases offer the basis of a simple and versatile tool to study the spatial organization and dynamics of protein networks formed at mobile, lipid-decorated interfaces.  相似文献   
3.
The aim of this study was to evaluate the combined effects of liming and behaviour of Sarcocornia fruticosa as a strategy of phytomanagement of metal polluted salt marsh soils. Soils were taken from two polluted salt marshes (one with fine texture and pH~6.4 and the other one with sandy texture and pH~3.1). A lime amendment derived from the marble industry was added to each soil at a rate of 20 g kg(-1), giving four treatments: neutral soil with/without liming and acidic soil with/without liming. Cuttings of S. fruticosa were planted in pots filled with these substrates and grown for 10 months. The pots were irrigated with eutrophicated water. As expected, lime amendment decreased the soluble metal concentrations. In both soils, liming favoured the growth of S. fruticosa and enhanced the capacity of the plants to phytostabilise metals in roots.  相似文献   
4.
Cis-Dichloro(diaminosuccinic acid)palladium(II), cis-[Pd(H2dasa)Cl2] (I), or cis-dichloro(diaminosuccinate diethyl ester)palladium(II), cis-[Pd(Et2dasa)Cl2] (II) reacts with two equivalents of AgClO4 to give insoluble Pd(dasa) or an aqueous solution of [Pd(Et2dasa) (H2O)2](ClO4)2, respectively. Three solutions of this salt were titrated with NaOH (I = NaClO4 (0.15M),37 degrees C), and 133 E(H+) data (3.5 < or = pH < or = 7) were treated by SUPERQUAD to fit log beta pqr of cis-aquahydroxo-(pqr = 10-1, -5.25(3)) and di-mu-hydroxo-species (20-2, -6.55(1)). At pH > 7 the ester hydrolysis prevents the calculation of log beta 10-2 for the cis-dihydroxo-complex. Another three solutions of such salt were titrated (I = 0.15M (NaClO4), 37 degrees C) with NaOH and NaCl simultaneously using two potentiometric systems (which measure H+ or Cl-). From 147 E(H+) and E(Cl-) data pairs and the above fixed log beta pqr, SUPERQUAD calculations yield log beta pqr for cis-chloro-aqua (pqr = 110, 3.65(1)), cis-chloro-hydroxo (11-1, -2.68 (4)), and cis-dichloro-species (120, 5.86(3)). Simulated and experimental titrations are in good agreement. Circular dichroism spectra of native DNA and drug:DNA complexes suggest that cis-Pd(H2dasa) and cis-Pd(Et2dasa) chelate moieties induce an opening and rotation of the stacked bases in the double helix. This finding is explained by the abundance of each one and of the total neutral and charged species of II in the tested CD solution.  相似文献   
5.
We report the irradiation of TiO(2) suspensions containing Br(-) and dissolved organic carbon (DOC). In the absence of DOC, we found no evidence for the formation of BrO(3)(-) upon irradiation of 1gL(-1) P25 suspensions with UV light for initial Br(-) concentrations up to 10mgL(-1). In the presence of DOC (Lake Hohloh, Germany and salicylic acid), we found no evidence for the formation of either BrO(3)(-) or trihalomethanes (THMs). However, small amounts of adsorbable organic halogen (AOX) were formed at high bromide concentrations (3mgL(-1)). When irradiating P25 suspensions containing bromide and 2,4-dihydroxybenzoic acid (DHBA, high bromoform formation potential), we observed the formation of significant amounts of bromoform (up to 10microgL(-1)). Bromoform appeared only after the DHBA had been degraded.  相似文献   
6.
The socio-economic and ecological impacts of selected projects of the BMBF funding program “r4 – Innovative Technologies for Resource Efficiency – Research for the Provision of Raw Materials of Strategic Economic Importance” are presented. Many, but not all, research projects indicate a potential improvement of the supply situation in Germany. In some cases, the provision of secondary raw materials is unprofitable or ecologically detrimental. These cases require a balancing between security of supply and other economic and ecological objectives.  相似文献   
7.
The degradation of natural organic matter (NOM) in homogeneous and heterogeneous advanced oxidation processes (AOP) was simulated using a simple underlying physical model. By treating the NOM molecules as linear chains and allowing them to be cleaved at any point selected at random, it is possible to reproduce well the results for homogeneous AOP experiments.To simulate a heterogeneous process, a bias was introduced (in the form of different weights for different chain lengths) according to literature data on the adsorption of NOM onto TiO2 nanoparticle agglomerates. After introduction of the (adsorption) bias, the simulation closely followed the degradation sequence observed in heterogeneous photocatalysis with TiO2 suspensions.Thus, the experimental results for homogeneous AOP may well be explained by a random breakdown of the NOM molecules; that is, we find no evidence for a selective degradation of the large molecular size material. However, a selectivity is present in the heterogeneous system due to the differential adsorption of NOM onto the reactive surface.  相似文献   
8.
This study reports on the synthesis of novel bioceramic composite coating of hydroxyapatite (HA) reinforced with carbon nanotubes (CNTs) and aluminum oxide (Al2O3) using plasma spray technique. Fracture toughness of HA–20 wt.% Al2O3 improved by 158% as compared to HA coating whereas HA–18.4 wt.% Al2O3–1.6 wt.% CNT showed an improvement of 300%. Carbon nanotubes provided reinforcement via rebar mechanism. Human fiber osteoblast cell-growth studies showed that biocompatibility of the coating remained unaltered, as Al2O3 retained its bio-inertness and CNT, its bioactivity, within the composite coatings. Composite coating showed lower attachment, but higher proliferation rate, for the osteoblast cells, which has been attributed to the surface roughness. An optimized relation between coating composition, its biocompatibility and mechanical properties was established to predict the most suited coating material for orthopedic implants. HA–Al2O3–CNT composite coating displayed most improved mechanical properties while retaining its biocompatibility.  相似文献   
9.
Living systems tend to have non‐normal behaviors, are autocorrelated, exhibit patterns of growth or decrement, and achieve states of dynamic equilibrium, making them hard to manage. One way to manage and improve these complex systems is by identifying assignable causes of variation whenever they occur, and control charts are one of the most known tool for those situations. However, in the presence of sustained changes, control charts are not capable of telling the initial moment of a change. This paper proposes a nonparametric estimator capable of dealing with non‐normal observations heterocedastic over time. The median test is used to estimate the time of a step change in Shewhart Control Charts using a relatively successful approach based on a binary segmentation approach. Furthermore, an application is developed to deal with changes on the trend of processes fitting a random walk with drift. Performance is evaluated with extensive Monte Carlo simulations, and results are compared with the maximum likelihood estimator for normal series of independent observations. Results showed acceptable performance when normality is not met and robustness under heterocedasticity. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
10.
The Beam Mode Expansion (BME) approach for corrugated conical feed horn plus meniscus lens is presented. This approach is useful for providing the radiation pattern as it propagates through an optical system. A developed theoretical model has been verified measuring near and far field of a built horn and lens. These results have been used for designing the optical system of a Cassegrain antenna at 100GHz using the fundamental Gaussian beam mode (GBM) of the new approach. Multimode analysis has been performed with the pre-designed system in order to test the fundamental GBM results.  相似文献   
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