Response of the seated human body to whole-body vertical vibration: discomfort caused by sinusoidal vibration

Frequency weightings for predicting vibration discomfort assume the same frequency-dependence at all magnitudes of vibration, whereas biodynamic studies show that the frequency-dependence of the human body depends on the magnitude of vibration. This study investigated how the frequency-dependence of vibration discomfort depends on the acceleration and the force at the subject–seat interface. Using magnitude estimation, 20 males and 20 females judged their discomfort caused by sinusoidal vertical acceleration at 13 frequencies (1–16 Hz) at magnitudes from 0.1 to 4.0 ms^? 2 r.m.s. The frequency-dependence of their equivalent comfort contours depended on the magnitude of vibration, but was less dependent on the magnitude of dynamic force than the magnitude of acceleration, consistent with the biodynamic non-linearity of the body causing some of the magnitude-dependence of equivalent comfort contours. There were significant associations between the biodynamic responses and subjective responses at all frequencies in the range 1–16 Hz.

Practitioner Summary: Vertical seat vibration causes discomfort in many forms of transport. This study provides the frequency-dependence of vibration discomfort over a range of vibration magnitudes and shows how the frequency weightings in the current standards can be improved.     

浅谈环保型助溶剂丙二醇醚的现况与应用

简要介绍了丙二醇醚国内外现状以及丙二醇醚的环保性评价和用途。     

S-苄基-L-半胱氨酸的合成

由溴化苄和L-半胱氨酸直接合成S-苄基-L-半胱氨酸,通过正交试验及统计分析,检验了各影响因子的显著性,确定了最佳工艺条件为：反应时间2.5h,反应温度45℃,原料配比n（溴化苄）：n（L-半胱氨酸）=1：1.在此条件下反应,摩尔产率可达到95%.     

Effect of miscibility and forced compatibility on damping properties of CIIR/PAc blend

In this study, a kind of novel damping materials was prepared based on the blend of chlorinated butyl rubber (CIIR) and polyacrylate (PAc) synthesized by different molar ratio of butyl methacrylate and ethyl acrylate. Research results from experiments and analyses by employing DMA, TEM, and FTIR show that whether at a cocured system or noncocured system, it can be achieved to shift a loss peak of CIIR towards a higher temperature region and to keep the damping value from markedlly decreasing, which broadens the effective damping function area of CIIR to the vicinity of ambient temperature. In the former system, the thermodynamical miscibility of CIIR and PAc, to some extent, is predominated by the molecular design of PAc, while in the latter system, covulcanized networks play a more significant role in improving compatibility and abating the peak split, though the suppression effect of thermal stress on the transition of CIIR T_ll transition still can not be neglected. Furthermore, transition state derived from the cocuring CIIR and PAc cannot make the phase separation completely take place, and consequently results in the deformation of phase morphology of the cocured CIIR/PAc blend. It is the influence of thermodynamics miscibility and forced compatibility in different size that makes the suppression effect of foreign PAc on CIIR T_ll transition be controllable. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3127–3133, 2006     

反相微乳液法制备高溶度ZrO2陶瓷墨水(Ⅰ)

尝试采用新颖的反相微乳液法制备陶瓷墨水，为了获得高溶度陶瓷墨水，对反相微乳液体系优选进行研究，着重就Triton x-100/醇／烷／水体系，采用目测法，分光光度法，电导率法和离心分离法，分别考察了不同醇，烷配伍时体系的稳定性和相关物理性质，根据这些性质是否突变以确定体系是否发生相变，给出了体系拟三元相图。实验表明，在20℃时Triton x-100／正己醇／环己烷／水反相微乳液体系表现优异，当Triton x-100与正醇的质量比为3：2时达到最大范围的反相微乳液区，最大溶水量时的最佳组成为Triton x-100:正己醇：环己烷：水＝19．1％：12．8％：23．7％：44．4％（质量比）。     

Cu2O-CuAlO2-Cu基金属陶瓷导电性能研究

通过热压技术制备Cu2O-10CuAlO2-xCu金属陶瓷材料，并对其导电性能进行了研究。结果表明，Cu2O-10CuAlO2-xCu在Cu含量超过15wt．％后呈金属导电性。材料的微观结构观察及物理性能测试表明，金属陶瓷材料的电导率不仅取决于材料的金属相含量，还取决于金属相颗粒尺寸和孔隙率的大小。材料中金属相的颗粒尺寸取决于热压工艺参数，随着热压温度的升高而增大，但随热压压力的升高而减小。     

三聚氰胺的改性及其应用

综述了三聚氰胺对脲醛树脂、酚醛树脂的改性以及改性三聚氰胺在涂料、板材等方面的应用。三聚氰胺可以和其它聚合物发生聚合反应,形成立体网状结构,提高聚合物的强度、韧性、阻燃性等。三聚氰胺可作为改性剂对许多聚合物进行改性,以提高其性能。     

Face detection by structural models

Despite the successes in the last two decades, the state-of-the-art face detectors still have problems in dealing with images in the wild due to large appearance variations. Instead of leaving appearance variations directly to statistical learning algorithms, we propose a hierarchical part based structural model to explicitly capture them. The model enables part subtype option to handle local appearance variations such as closed and open month, and part deformation to capture the global appearance variations such as pose and expression. In detection, candidate window is fitted to the structural model to infer the part location and part subtype, and detection score is then computed based on the fitted configuration. In this way, the influence of appearance variation is reduced. Besides the face model, we exploit the co-occurrence between face and body, which helps to handle large variations, such as heavy occlusions, to further boost the face detection performance. We present a phrase based representation for body detection, and propose a structural context model to jointly encode the outputs of face detector and body detector. Benefit from the rich structural face and body information, as well as the discriminative structural learning algorithm, our method achieves state-of-the-art performance on FDDB, AFW and a self-annotated dataset, under wide comparisons with commercial and academic methods.     

高耐蚀性Zn—Co合金镀层钝化工艺的研究

研究了电镀Zn-Co合金镀层的钝化液的组成及工艺条件，溶液各成分及工艺条件对钝化膜质量的影响，通过几种腐蚀试验方法，测量了钝化膜的耐蚀性，结果表明，研究的钝化工艺可以得到耐蚀性良好的钝化膜。     

An Attractive Synthetic Approach to Methyl Formate from Methanol via Methyl Nitrite

Catalytic synthesis of methyl formate has been investigated by a novel route starting from methyl nitrite in vapor phase. The acidic sites of the catalysts play a crucial role for the catalytic activity and the selectivity of formation of methyl formate. The H-Y zeolite catalyst gave higher yield and selectivity of the target product. This study provides a new approach for the synthesis of methyl formate from methanol via methyl nitrite.