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排序方式: 共有709条查询结果,搜索用时 15 毫秒
1.
The aim of this study is to explore whether lung cancer associated with air pollution has cell type specificity. The air quality data (SO(2), CO, O(3), NOx) from the Taiwan EPA's air quality monitoring stations were collected between 1995 and 1998. Patients with lung cancer were identified through the National Cancer Registration Program operated by the Taiwanese government. Two major pathological types (adenocarcinoma (AC) and squamous cell carcinoma (SCC)) were considered. The Pearson correlation coefficients between the air quality index and age-standardized incidence rate per 100,000 person years (ASR) of AC and SCC were calculated for both genders for three township categories characterized by different levels of air pollution. The traffic-related NOx and CO showed significant correlations with female lung cancer incidence rate, with Pearson's correlation 0.33 (P=0.03) and 0.40 (P=0.01) respectively. However, the correlation between air pollution and lung cancer was not significant for males. Significant correlation coefficients were also found between the ratio of AC/SCC and the mean concentrations of NOx (r=0.41, P=0.04) and CO (r=0.47, P=0.02) in females. Our results show that the worse the air pollution was in the area, the higher the AC rate, regardless of gender. On the other hand, SCC incidence rates did not increase with increasing air pollution. Our results show that a correlation exists between air pollution and lung adenocarcinoma incidence. 相似文献
2.
Ozonation of Pyrolytic Aqueous Phase: Changes in the Content of Phenolic Compounds and Color 下载免费PDF全文
Shi‐Shen Liaw Oselys Rodriguez Justo Victor Haber Perez Shuai Zhou Manuel Garcia‐Perez 《化学工程与技术》2016,39(10):1828-1834
Ozonation on the phenols present in pyrolytic aqueous phases attained from biomass thermochemical conversion was evaluated. During ozonation, the dark color of original samples was found to decrease as a function of ozonation time. The oxidation kinetics of phenols was quantified by a method based on the color changes of samples. The oxidation profiles showed different behaviors and in some cases the phenols presented a positive correlation with the relative R color parameter, except eugenol, syringol, and vanillin which were markedly different. Finally, the color changes observed seem to be associated with the changes in the overall content of phenols and with the change in the molecular weight of the heavy fractions that include lignin oligomers. 相似文献
3.
Shenyan Huang Gautam Ghosh Xin Li Jan Ilavsky Zhenke Teng Peter K. Liaw 《Metallurgical and Materials Transactions A》2012,43(10):3423-3427
Ultra-small-angle X-ray scattering (USAXS) is employed to quantify the average size, interparticle spacing, and volume fraction of the primary B2 precipitates in Fe-based superalloys with varying Al concentration. The results are analyzed with a model incorporating polydispersity and interference effects and verified by transmission electron microscopy (TEM) characterizations. As the Al amount increases from 4 to 10?mass pct, there is an approximately 40?pct decrease in the average interparticle spacing and?~30?pct reduction in the average particle diameter. 相似文献
4.
Due to rapid environmental change, policymakers no longer choose foresight issues based on their own experience. Instead, they need to consider all the possible factors that will influence new technological developments and formulate an appropriate future technological development strategy to the country through the technology foresight system. For the sake of gathering more objective evidence to convince stakeholders to support the foresight issues, researchers can employ bibliometric analysis to describe current scientific development and forecast possible future development trends. Through this process, a consensus is reached about the direction of future technology development. However, we believe that bibliometric analysis can do more for technology policy formulation, such as (1) offer quantitative data as evidence to support the results of qualitative analysis; (2) review the situations of literature publication in specific technological fields to seize the current stage of technology development; and (3) help us grasp the relative advantage of foresight issues development in Taiwan and the world and develop profound strategic planning in accordance with the concept of Revealed Comparative Advantage. For those reasons, our research will revisit the role that bibliometric analysis plays for nations while choosing the foresight issues. In addition, we will analyze the development of the technology policy in Taiwan based on bibliometric analysis, and complete the foresight issues selection by processing key issue integration, key word collection related to this field, the searching and confirmation of literature, development opportunities exploration, comparative development advantage analysis and the innovation-foresight matrix construction, etc. 相似文献
5.
6.
Der-Cherng Liaw 《International journal of control》2013,86(3):206-214
Issues of asymptotic stabilization of a class of non-linear driftless systems are presented. In addition to the necessary and sufficient condition for the existence of a smooth time-invariant asymptotic stabilizer, sufficient condition for the existence of a quadratic-type Lyapunov function candidate is also proposed herein to alleviate the construction of stabilizing control laws. Following the deduction of the equivalence of the sufficient condition and the determination of the local definiteness of a defined scalar function, the stabilizability checking conditions are then derived in terms of system dynamics and its derivatives at the origin only. These are achieved by taking Taylor's series expansion on system dynamics. The derived conditions are shown to be consistent with those obtained by Brockett. Comparative results of Liaw and Liang are also included. Finally, examples are given to demonstrate the use of the main results. 相似文献
7.
Wu Kai Yuan-Hao Wu Wei Shen Chen Rong-Tan Huang Haoling Jia Peter K. Liaw Tao Zhang 《Metallurgical and Materials Transactions A》2012,43(8):2721-2728
The oxidation behavior of a [(Co50Cr15Mo14C15B6)97.5Er2.5]93Fe7 bulk-metallic glass (Co7-BMG) was studied over the temperature range of 873?K to 973?K (600?°C to 700?°C) in dry air. The oxidation kinetics of the Co7-BMG generally followed the parabolic-rate law, as its oxidation rates increased with temperature. The scaling rate of the Co7-BMG was significantly lower than that of pure Co, which indicates a better oxidation resistance for the amorphous alloy. The scales formed on the Co7-BMG consisted mostly of CoMoO4 and Co3O4, as well as minor amounts of CoO, Cr2O3, and uncorroded Co3B. The formation of CoMoO4 and Cr2O3 is responsible for the lower oxidation rates of the glassy alloy with respect to those of pure Co. In addition, the presence of Co3B further indicated that the crystallization of the amorphous substrate during the oxidation was taken place. 相似文献
8.
Yun‐Hsuan Huang Shu‐Hsien Huang Wei‐Chi Chao Chi‐Lan Li Yun‐Ying Hsieh Wei‐Song Hung Der‐Jang Liaw Chien‐Chieh Hu Kueir‐Rarn Lee Juin‐Yih Lai 《Polymer International》2014,63(8):1478-1486
To improve the pervaporation performance in separating an aqueous ethanol solution, polyamide thin‐film composite (TFC) membranes (m‐tolidine‐H‐TMC/mPAN) were prepared through the interfacial polymerization reaction between trimesoyl chloride (TMC) and 2,2'‐dimethylbenzidine hydrochloride (m‐tolidine‐H) on the surface of a modified polyacrylonitrile (mPAN) membrane. The effects of the feed ethanol concentration on the pervaporation performance and the durability of m‐tolidine‐H‐TMC/mPAN TFC membranes were investigated. To choose the optimal mPAN membrane as the TFC substrate, the effect of hydrolysis time on the chemical properties and separation performance of an mPAN substrate was also studied. An appropriate hydrolysis time of 15 min was chosen to obtain the mPAN substrate due to the corresponding high permeation flux. The m‐tolidine‐H‐TMC/mPAN TFC membrane exhibited a high pervaporation performance for ethanol dehydration. A positron annihilation lifetime spectroscopy experiment was used to estimate the mean free‐volume radius of the m‐tolidine‐H‐TMC polyamide selective layer, which lay between the radii of the water and ethanol molecules. © 2013 Society of Chemical Industry 相似文献
9.
Yu-Hao Lee Tsun-Cheng Wu Chao-Wu Liaw Ten-Chin Wen Shih-Wei Feng Jey-Jau Lee Yao-Ting Wu Tzung-Fang Guo 《Organic Electronics》2013,14(4):1064-1072
This work studies a series of fluorescent materials, benzo[k]fluoranthene-based linear acenes, and uses these materials directly as the non-doped active layer to fabricate deep blue- to green-emissive organic light emitting diodes (OLEDs). Experimental results indicate that benzo[k]fluoranthene-based linear acenes with different substituents in pristine films have a wide range and strong intensity of the luminescence spectra. The substituents of benzo[k]fluoranthene derivatives modulate the lifetime of the excited state and PL spectra of excitonic, excimer or both emissions in the solid state. Controls of emission spectra are exploited in fabricating high-performance non-doped deep blue to green OLEDs with electroluminescence in the deep blue region (420–460 nm), green region (480–580 nm) or both (430–580 nm). 相似文献
10.
R.L. McDaniels L. Chen R. StewardP.K. Liaw R.A. BuchananSteve White Kevin Liaw D.L. Klarstrom 《Materials Science and Engineering: A》2011,528(12):3952-3960
The strain-controlled fatigue behavior of the new nickel-chromium-molybdenum superalloy, HASTELLOY® C-2000® was investigated. Low-cycle fatigue specimens were tested in strain-controlled fatigue conditions under axial strain range control at 24 °C, 204 °C and 427 °C. The results indicated that at total strain ranges below 0.8%, temperature does not significantly influence fatigue life, whereas at high total strain ranges, there is a significant drop in fatigue life at 427 °C. At room temperature and 204 °C, the cyclic stress response was cyclic hardening, followed by cyclic stability, cyclic hardening, or cyclic softening, depending on the total strain range. At 427 °C, only cyclic hardening was observed. Fractographic and metallographic analyses were also conducted. The strain-life and Holloman relation parameters are calculated. A theoretical model that predicts the life of this alloy under the tested conditions using the plastic strain energy method is also presented. The results of the theoretical model are in good agreement with the experimental results. 相似文献