Effects of the reduced toxicity of car exhaust on accidental deaths: a comparison of the United States and Great Britain

A study of the frequency of car exhaust as a cause of accidental death in the United States from 1968 to 1984 showed that the accidental death rate from car exhaust has declined during the same period during which the toxicity of car exhaust has been reduced through the imposition of emission controls. However, in Great Britain, where there are no emission controls on cars, the accidental death rate from car exhaust has risen slightly over the same period. Thus, the introduction of emission controls on cars to reduce pollution of the environment seems to have had incidental beneficial effects on mortality from accidental poisoning from car exhaust.     

基于小波高阶统计量的数字图像来源取证方法

目的为了识别图像来源于相机还是其他电子设备,提出一种基于小波高阶统计量的图像来源取证方法。方法利用生成途径对图像性质的影响和数理统计方法,通过对比不同来源的数字图像的生成途径对它们各自性质的影响,从图像的多尺度分析角度,研究不同来源的图像在变换域所呈现的独有特性,提取数字图像小波域的高阶统计特征,以此判断图像的来源。结果实验结果表明,针对计算机软件、数码相机和扫描仪这3类图像的平均测试正确率达到了97.9%。结论该方法在确定图像来源上有较高的效率和准确率。     

Depolarization of autofluorescence from malignant and normal human breast tissues

We report on steady-state measurements on the anisotropy of autofluorescence from malignant and normal breast tissue as a function of tissue thickness. For thin tissue sections the anisotropy from normal tissue was found to be smaller compared with that from malignant tissue. However, the opposite result was obtained for thicker tissues. A phenomenological model was also developed to simulate the dependence of anisotropy on tissue thickness.     

Application of holography in jet acoustic studies

Source strength distribution on a jet boundary was obtained from measurements using the principle of acoustic holography. Measurements were conducted in an open field. Measurement of acoustic pressure on a cylindrical two-dimensional contour located close to the vibrating jet boundary was used to obtain the acoustic source strength distribution at the jet boundary. Particular attention was focussed on back projection of the sound field on to a cylindrical surface. A jet emanating from 5 mm convergent nozzle was used for the holography experiments, assuming axisymmetry. Experimental results were compared with results obtained from holography     

Influence of vibration on heat and mass transfer in a capillary-porous material

This paper presents the results of an experimental study of the influence of vibration (frequency from 20 to 60 cps, double amplitude from 1.1 to 3. 6 mm) on the rate of drying of capillary-porous material, and on the motion of moisture in a single capillary vibrating at a frequency of from 10 to 80 cps.     

Determination of fracture toughness and energy dissipation of SiO2-poly(methyl metacrylate) hybrid films by nanoindentation

In this paper we have applied different methods based on nanoindentation techniques to measure the toughness of SiO₂-poly methyl-methacrylate hybrid films on organic acrylic substrates. The hybrid films were deposited by the Sol-Gel method from precursor solutions containing tetraethyl-orthosilicate, methylmethacrylate and 3-trimethoxysilyl propyl methacrylate (TMSPM) as the coupling agent. The influence of TMSPM content in the hybrid precursor solution on the fracture behavior of the hybrid films was studied. The classical indentation crack length method was applied from nanoindentation tests to determine the stress intensity factor by direct measurement of crack length from atomic force microscopy images. A second method, based on the pop-in analysis allowed the separation of crack formation from film delamination from multiple pop-ins. Finally, a third method based on energy methods is also reported and discussed. The amount of TMSPM in the precursor solution showed a strong influence on the toughness of the hybrid films.     

Sorption of copper(II) onto super-adsorbent of bentonite–polyacrylamide composites

In this work, bentonite embedded in the polyacrylamide (PAAm) gels was used as a novel adsorbent for the removal of Cu(II) from aqueous solution. The sorption and desorption of Cu(II) on bentonite–polyacrylamide (BENT–PAAm) was investigated as the function of pH, ionic strength, adsorbent content, Cu(II) concentrations and temperature. The results indicated that the sorption of Cu(II) on BENT–PAAm was strongly dependent on pH, ionic strength and temperature. The sorption increased from about 9% to 97% at pH ranging from 2.4 to 7. The sorption of Cu(II) on BENT–PAAm increased with increasing temperature and decreasing ionic strength. The sorption of Cu(II) on BENT and on BENT–PAAm was an endothermic and irreversible process. The results of desorption indicated that the adsorbed Cu(II) ions on solid particles were difficult to be desorbed from solid to liquid phase. From the comparison with BENT, BENT–PAAm showed higher sorption capacity with C_smax increasing from 29 to 33 mg/g at pH 6.2 and from 11 to 20 mg/g at pH 5.0 for the sorption of Cu(II) from BENT to BENT–PAAm composites. The average standard enthalpy change (ΔH°) and the entropy change (ΔS°) of Cu(II) sorption on BENT–PAAm are higher than those of Cu(II) sorption on BENT. The BENT–PAAm composites can be used as a super-adsorbent for the removal of Cu(II) from aqueous solution.     

Structure and physical properties of undoped ZnO and vanadium doped ZnO films deposited by pulsed laser deposition

Undoped ZnO films were deposited using pulsed laser deposition technique on Si and glass substrates in different O2 partial pressures (ranging from 10(-5) mbar to 3 mbar) and substrate temperatures. When the substrate temperature is 500 degrees C and O2 partial pressure (pp) approximately 3 mbar, randomly oriented ZnO hexagons were observed on glass substrate, whereas, dense ZnO hexagonal rod like structures (diameter ranging from 200-500 nm) were observed on Si substrate. The photoluminescence (PL) characterization of ZnO film grown on Si exhibited an intense defect free narrow excitonic emission in the UV region (Full width half maximum (FWHM) approximately 11.26 nm) as compared to broad emission (FWHM approximately 57.06 nm) from that grown on glass. The parent film emission was found to shift from UV to blue region on doping ZnO with Vanadium.     

电沉积条件对Fe-Ni-P合金沉积的影响

为促进Fe-Ni-P合金电沉积层在信息存储材料和屏蔽材料中的应用,研究了pH值、电流密度等工艺条件对合金沉积速度、组成、表面形貌和结构的影响.结果表明:当镀液主盐物质的量比Fe/Ni=5/5时,随pH值从2.0增加到4.0,镀层中Fe原子分数从6.92%增加到64.47%,Ni从61.03%下降到8.07%,P从32.05%下降到27.46%;随电流密度从20 mA/cm2增加到50 mA/cm2,镀层中Fe原子分数从2.49%增加到63.15%,Ni从55.99%下降到13.50%,P从41.52%下降到23.35%.用X射线衍射和扫描电镜研究了镀层的结构和表面形貌,试验表明,所有镀层均呈非晶态结构,受工艺条件影响较小;随pH值从2.0增加到4.0,镀层表面的圆形颗粒粒径逐渐增大.     

The Application of Multiresponse Estimation to Drug Stability Studies

This paper focuses on the statistical methodology for the simultaneous analysis of stability data obtained on both parent compound and degradation products. A mathematical model based on kinetic theory is developed to describe both the disappearance of parent compound and appearance of degradation products. Analysis of data obtained from accelerated testing of drug stability is accomplished by extending the kinetic model to include the Arrhenius relationship. A simulated data set generated from parameter estimates obtained from an actual analysis is used as an example to illustrate the statistical techniques.     

Environmental applications of gas chromatography/atomic emission detection

A gas chromatograph/atomic emission detector (GC/AED) system has been evaluated for its applicability to environmental analysis. Detection limits, elemental response factors, and regression analysis data were determined for 58 semivolatile environmental contaminants. Detection limits for injected analytes ranged from 0.17 to 3.0 ng on the hydrogen 486-nm channel, from 1.0 to 5.0 ng on the nitrogen 174-nm channel, from 0.65 to 11.7 ng on the oxygen 777-nm channel, from 0.071 to 3.0 ng on the chlorine 479-nm channel, and from 0.023 to 0.038 ng on the sulfur 181-nm channel. Mean elemental response factors (ERFs) measured on these channels, relative to the carbon 496-nm channel, were hydrogen, 0.084 (mean %RSD = 6.6); nitrogen, 0.246 (mean %RSD = 19); oxygen, 0.459 (mean %RSD = 16); and chlorine, 0.417 (mean %RSD = 3.6). The higher precision obtained for hydrogen and chlorine, relative to that for nitrogen and oxygen, is attributed to the ability to scan these elemental channels in the same GC run as the carbon 496-nm channel (diode array wavelength range limitation of ～40 nm/run). Mean ERFs of standard compounds were used to determine the molecular formulas of chlorinated hydrocarbons and chlorinated organosulfur compounds in a contaminated environmental soil sample. These formulas are in good agreement with the molecular weights and chlorine isotopic data obtained from low-resolution gas chromatography/mass spectrometry.     

Fatigue crack closure: From LCF to small scale yielding

Most of the research on crack closure has been devoted to crack propagation under small scale yielding. In this paper, the effect of different length scale from micro-crack to long cracks and different loading conditions from low cycle fatigue, LCF, to small scale yielding on crack closure are considered. The main focus is on LCF crack closure behaviour which is studied by in situ fatigue experiments in a scanning electron microscope. The results demonstrate the importance of crack closure for the explanation of the LCF behaviour. The change of crack closure from LCF to high cycle fatigue and their consequences for lifetime prediction will be discussed.     

Far-ultraviolet reflectance measurements and optical constants of unoxidized aluminum films

The far-UV reflectance of thin unoxidized aluminum films prepared and maintained in ultra-highvacuum conditions was measured versus the angle of incidence, and the complex refractive index was obtained from those measurements on several wavelengths from 82.6 to 113.5 nm. Measurements were made on two perpendicular planes of incidence to deal with the unknown of the polarization state of the radiation beam. The surface roughness was characterized by atomic force microscopy. The refractive index is obtained for the first time, to our knowledge, from direct optical measurements in this spectral range. Current results match well the former values in the literature that were calculated through the Kramers-Kronig analysis by using in the above interval reflectances estimated from electron-energy-loss spectra and from optical measurements on surfaces of unstated roughness.     

Method for measuring the melting temperature of gold nanoclusters on substrate surfaces

Results are reported from a study of low-energy electron scattering on Au nanoclusters on substrates of amorphous SiO₂ film and polycrystalline Ni at room temperature. When the height of the Au nanoclusters is reduced from 5 to 1 nm, their melting temperature is found to decrease from 1337 K (metallic gold) to 500 K. A simple method is proposed for measuring the thermodynamic characteristics (melting temperature and Debye temperature) of metallic nanoclusters on substrate surfaces.     

Selective recovery of uranium from multicomponent salt systems on inorganic sorbents

The recovery of uranium from highly saline process solutions from extraction refining of uranium on Termoksid inorganic sorbents was studied under static and dynamic conditions. The isotherms of uranium sorption on these sorbents are described by the Freundlich equation. Termoksid inorganic sorbents proved to be efficient for exhaustive removal of uranium from process solutions from extraction refining of uranium.     

Thermal expansion and heat capacity of GaAs and InAs

Thermal expansion of GaAs and InAs was measured in the temperature ranges from 396 to 1149 and from 441 to 1206 K, respectively. The thermal-expansion coefficients, Debye temperatures, and root-meansquare atomic displacements were calculated. These parameters were found to depend on the root-mean-square atomic weights of the compounds. Based on the published data and our heat capacity measurements on GaAs and InAs, the coefficients appearing in the equation for the temperature dependence of heat capacity in the temperature ranges from 200 K to the melting points of GaAs and InAs were determined     

Infrared spectral investigation of polyacrylate adsorption on alumina

Diffuse reflectance infrared Fourier transform spectroscopy was used to investigate the structural nature of polyacrylates adsorbed on alumina from aqueous solution. The presence of sodium bicarbonate or sodium ions on the alumina surface could inhibit the carboxylate groups on the polymer chains from forming covalent bonds with aluminium ions on the surface. More carboxylate groups of the chains were adsorbed on surface sites at lower polymer concentration and higher pH. Also, an increased loop formation of the polyacrylate chains occurred with a decrease in treatment of pH and an increase in polymer concentration. When the pH changed from higher to lower values in steps, the adsorbed polymer did not increase as much from the stretched-out form to the coiled form as was noted if one initially only treated the aqueous polyacrylate/alumina slurry at the lower pH. The adsorption of water on the polyacrylate-treated surface changed the ratio between covalently and ionically bonded carboxylate groups, causing more ionically bonded species.     

Effect of temperature on the growth of InAs/GaAs quantum dots grown on a strained GaAs layer

We have studied the effect of temperature on the growth of InAs quantum dots (QDs) grown on a strained GaAs layer. The 2.0 nm thick, strained GaAs was obtained by growing it on a relaxed In0.15Ga0.85As layer. We observed that the density of QDs grown in this manner strongly depends on the growth temperature. A change in the growth temperature from 510 degrees C to 460 degrees C resulted in a large increase in the QD density from 2.3 x 10(10) cm(-2) to 6.7 x 10(10) cm(-2) and a sharp reduction in their height from 8.0 nm to 3.0 nm. Photoluminescence (PL) results from these QDs are also presented.     

20世纪早期躺椅的设计演变及历史编纂学分析

探讨20世纪初期在英国、欧洲大陆和美国发生的从理疗躺椅到现代躺椅的设计演变，并分析不同历史时期史学家们对相关概念的认识转变。通过历史编纂学的研究方法从3个角度进行梳理和论证。首先从文化维度分析人们对斜躺姿势和“舒适”概念的认识转变，其次从生理科学维度看人体工程学角度下椅子与人体的关系，最后从社会维度针对现代躺椅作为现代主义标签这一现象在物质文化研究方法论层面进行反思。从文化史、科技史角度将各时期史学家对斜躺姿势、“舒适”概念与人椅关系的观点发展进行系统梳理，有助于避开传统的现代设计史研究视角，对躺椅的设计演变进行更为多元的探讨和理解。     

可持续性产品设计的创新方法与案例解析

目的拓展可持续性产品设计的思路,解析不同类别的可持续性产品设计案例,探讨可持续性产品设计的创新方法及其在设计实践中的应用。方法通过对典型案例的剖析,从"末端治理"来分析废弃物再利用的设计,从"源头干预"来分析产品全生命周期设计,从"共享服务"来分析产品与服务系统设计,从"消费公平"来分析弱势群体的社会和谐设计,从而归纳可持续性产品设计的创新方法。结论可持续性产品设计创新方法必须将关注重点从生产领域扩展到消费领域,从实体产品扩展到产品服务系统,从物质文化领域扩展到精神文化领域。可持续性产品设计的内容,应该同时关注产品的"生产系统"与"消费系统",将产品与服务系统有机融合,提升产品的使用效率与生态品质,促进全社会的消费公平,体现设计的经济价值与人文价值,为人类社会的永续发展贡献设计的力量。