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Biomedical and Environmental Sciences 1990年第1期3卷 90-98页

作者： j. q. HUANG Institute of Preventive Medicine Shanghai Medical University Shanghai 200032 China

The dose-response relationship for asbestos exposure in a chrysotile product factory was studied. The past gravimetric dust concentration values, obtained from different worksites, were converted into fiber concentration values according to conversion factors that were worked out by simultaneous sampling in this study. The conversions were made so that exposure could be expressed in fiber-years (f-yr). Asbestosis was diagnosed on the basis of chest radiographs and occupational histories. Cumulative dust exposure (f-yr) was calculated up to the date of diagnosis for asbestosis patients, and up to September 1982 for the remaining workers. A dose-response relationship expressed as fiber-years exposed vs cumulative prevalence of asbestosis was established by the life table method on the basis of these data. Predicted 3 and 1% prevalence of asbestosis corresponded to 43 and 22 f-yr exposure, respectively. Considering that a worker can work for 35 years, these doses are commensurate with dust concentrations of 1.22 and 0.63 f/ml, respectively. It is recommended that 1 f/ml be taken as the maximum allowable concentration of airborne asbestos dust for the workplace with an anticipated prevalence of about 2% asbestosis after 35 years of exposure. 1990 Academic Press, Inc.

关键词： A Study on the Dose-Response Relationship between Asbestos Exposure Level and Asbestosis among Workers in a Chinese Chrysotile Product Factory

Metal Dusting-Mechanisms and Preventions

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中国腐蚀与防护学报 2009年第4期29卷 262-276页

作者： j. q. ZHANG D. j. YOUNG School of Materials Science and Engineering University of New South Wales Sydney NSW 2052 Australia

Metal dusting attacks iron,low and high alloy steels and nickel-or cobalt-base alloys by disintegrating bulk metals and alloys into metal particles in a coke *** occurs in strongly carburising gas atmospheres(carbon activity a_C>1) at elevated temperatures(400℃～1000℃).This phenomenon has been studied for decades,but the detailed mechanism is still not well *** methods of protection against metal dusting are either directed to the process conditions-temperature and gas composition-or to the development of a dense adherent oxide layer on the surface of the alloy by selective ***,metal dusting still occurs by carbon dissolving in the base metal via defects in the oxide *** research work at UNSW is aimed at determining the detailed mechanism of metal dusting of both ferritic and austenitic alloys,in particular the microprocesses of graphite deposition,nanoparticle formation and underlying metal *** work was carried out using surface observation,crosssection analysis by focused ion beam and electron microscopic examination of coke deposits at different stages of the *** was found that surface orientation affected carbon deposition and metal dusting at the initial stage of the *** dusting occurred only when graphite grew into the metal interior where the volume expansion is responsible for metal disintegration and *** was also found that the metal dusting process could be significantly changed by alterations in alloy *** was found to affect the iron dusting process by destabilising Fe_3C but increasing the rate of carbon deposition and dusting,which q.estions the role of cementite in ferritic alloy *** adding copper to iron did not change the carburisation kinetics,cementite formation and coke morphology,copper alloying reduced nickel and nickel-base alloy dusting rates *** of these fundamental results to the dusting behaviour of engineering al

关键词：金属腐蚀氧化防护机械装置

STUDY OF THE INFLUENCE OF pH ON THE ELECTROCRYSTALLIZATION OF ZINC

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 497-504页

作者： Z. Zhang W.H. Leng j. q. Zhang Department of Chemistry Zhejiang University Hangzhou 310027 China State Key Laboratory for Corrosion and Protection Institute of Metal Reseach The Chinese Academy of Sciences Shenyang 110016 China

The influence of pH value of the electrolyte solution on the zinc electroplating process was studied by means of cyclic voltammetry and chronoamperometry approaches. The results shown that, under this experimental conditions and at high overpotentials, the nucleation of zinc is instantaneous, and the nuclear densities N increase with the overpotentials. While at low potentials, no distinguished nucleation current can be observed. High pH promotes the deposition either by drifting the initial depositing potential positively, or by increasing the depositing current through the change of the total charge of the adsorption process q.ds, i.e., thevstructure of electrochemical double layer.

关键词： zinc electroplating nucleation growth mechanism

A NEURAL NETWORK FOR WELD PENETRATION CONTROL IN GAS TUNGSTEN ARC WELDING

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Acta Metallurgica Sinica(English Letters) 2006年第1期19卷 27-33页

作者： C.S. Wu j. q. Gao Y.H. Zhao Institute of Materials j.ining Shandong University Jinan 250061 China

Realizing of weld penetration control in gas tungsten arc welding req.ires establishment of a model describing the relationship between the front-side geometrical parameters of weld pool and the back-side weld width with sufficient accuracy. A neural network model is developed to attain this aim. Welding experiments are conducted to obtain the training data set （including 973 groups of geometrical parameters of the weld pool and back-side weld width） and the verifying data set （108 groups）. Two data sets are used for training and verifying the neural network, respectively. The testing results show that the model has sufficient accuracy and can meet the req.irements of weld penetration control.

关键词： neural network weld penetration control back-side weld width,gas tungsten arc welding

ELECTROCHEMICAL STUDY ON THE LOCALIZED CORROSION OF TWO DIFFERENT TEMPER LY12 ALLOYS

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Acta Metallurgica Sinica(English Letters) 2005年第5期18卷 609-619页

作者： F.H. Cao L. Guo L.j. Zhang Z. Zhang j. q. Zhang Department of Chemistry Yuquan Campus Zhejiang University Hangzhou 310027 China State Key Laboratory for Corrosion and Protection of Metals Institute of Metal Research The Chinese Academy of Sciences Shenyang 110016 China

The corrosion behavior of two different aged LY12 alloys in EXCO （234g/L NaCl, 50g/L KNO3 0.1M HNO3） and MIL-H-600 （35g/L NaCl, 5g/L （NH4）2SO4） solutions were studied using electrochemical impedance spectroscopy （EIS） in conj.nction with SEM techniq.e respectively, and the pH variation of the above accelerated corrosion solution during materials corroding was also measured to characterize the corrosion processes. At the beginning of corrosion, EIS plots exhibited two capacitive arcs in the high freq.ency range （Cd） and mediate freq.ency range （ Cf） originating from the original corroded surface and the newly formed interface respectively, and a low freq.ency inductive loop due to the relaxation phenomenon of reaction intermediates. In the EXCO,solution, the EIS results showed that once the exfoliation corrosion occurred, the inductive loop disappeared. The results also showed that the exfoliation corrosion susceptibility of state T6 is much higher than that of state T3, but the intergranular corrosion susceptibility has a reverse order. Based on the relationship of EIS results with SEM and metalloscopy morphologies of the corroding substrates and physic-chemical meaning of EIS parameters, an index （Cf/Cd） has been proposed to characterize the extent of the localized corrosion, which variation tallies with the real corrosion extent correctly. Meanwhile, good agreement was found between the experimental results and the electrochemical model proposed and, good coherence between the electrochemical features and the distribution type of constituent particles of corroding material was observed.

关键词： electrochemical impedance spectroscope LY12 alloy exfoliation corrosion intergranular corrosion

LITHIUM ORDERING IN CHEMICALLY DELITHIATED Li_xCoO_2

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Acta Metallurgica Sinica(English Letters) 2006年第3期19卷 197-202页

作者： X. Liu W.H. Tian H.X. Yang Y. G. Shi j. q. Li Department of Materials Physics and Chemistry University of Science and Technology Beijing Beijing 100083 China Beij.ng National Laboratory for Gondensed Matter Physics Institute of Physics The Chinese Academy of Sciences Beijing 100080 Ghina

Chemical delithiated LixCoO2 （x=1, 0.7, 0.66 and 0.57） has been synthesized by using a strong oxidant, NaS2O8 .The structure investigations indicate that all the samples remain with hexagonal cells, which have expansion of c axis during Li extraction. Transmission electron microscopy （TEM） observations revealed the presence of superstructures arising from intercalated U-ordering corresponding to first-principle calculations. The measurements of the physical properties are also influenced by Li concentration.

关键词： LixCoO2 delithiated Li-ordering

Prophylactic Antibiotic Treatment during Hysteroscopy: A Systematic Review

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Open j.urnal of Obstetrics and Gynecology 2015年第3期5卷 163-166页

作者： j.nnie Wij.a Paul j. q. van der Linden Deventer Ziekenhuis Deventer The Netherlands

Background: Overall, the use of antibiotics is increasing. We noticed different practices amongst different hospitals in their prophylactic use of antibiotics during operative hysteroscopy. This review investigates whether there is sufficient evidence to recommend antibiotic prophylaxis in operative hysteroscopy. Methods: We performed a systematic search in “Pubmed” using “hysteroscopy” and “antibiotic” and “prophylaxis” as search items. We found 16 hits of which 4 were suitable to include in our review. Findings: In an included Cochrane review no conclusion was drawn since no articles could be included. A prospective study by Nappi?et al.?[1]?support the recommendation of the American College of Obstetricians and Gynaecologists not to prescribe routinely antibiotic prophylaxis in cases of hysteroscopic surgery. Bhattacharya?et al. conducted a prospective study that was ended prematurely. They conclude that there is no convincing evidence that prophylactic antibiotics are of value in hysteroscopy. A review by Morrill?et al. yielded no new data. Conclusion: We did not find a significant increase in clinical relevant infectious symptoms after hysteroscopy in women treated with or without antibiotic prophylaxis, although data are insufficient to draw a definite conclusion. Therefore, we suggest a prospective study is mandatory on this topic.

关键词： Antibiotic Prophylaxis Operative Hysteroscopy

Single　Freq.ency　Operation　of　Diode－pumped　Intracavity　Freq.ency　Doubled　Nd：YAG　Laser　With　Tilted　KTP　Crystal：　Theoretical　Study

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Chinese j.urnal of Lasers 1996年第3期B5卷 199-204页

作者： YAO j. q. YANG j. B. SHENG W.D. ZHENG Y.(Institute of Laser and Opto-electronics, Tian j.n University, Tianj.n 300072, China)ZHENG H. YANG H.G.(Institute of Physics, Academia Sinica, Beij.ng 100080, China) Tianj.n Univ Tianjin China

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关键词： single-freq.ency Nd:YAG laser diode-pumped intracavity freq.ency Doubling

Does magnesium sulfate increase the incidence of postpartum hemorrhage? A systematic review

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Open j.urnal of Obstetrics and Gynecology 2011年第4期1卷 168-173页

作者： Laura M. Héman Paul j. q. Van Der Linden 不详

The incidence of Postpartum Hemorrhage (PPH) is increasing in the western world. We hypothesize that magnesium sulfate (MgSO4) could be a contributing factor. MgSO4 might increase the incidence of PPH by induction of vasodilation, tocolytic effects, and effects on the blood like red cell deformity, platelet activity inhibition and a prolonged bleeding time. Based on these effects of MgSO4 a correlation with PPH is suspected. MgSO4 is widely used in the prevention of eclampsia. However, the working mechanism of this effective drug is largely unknown. We performed a systematic search to find all Randomized Controlled trials (RCTs) containing MgSO4 in preeclamsia as well as all MgSO4 studies with information on PPH. Titles, abstracts and references of publications were evaluated for appropriateness and whether they met the inclusion criteria. RCTs about MgSO4 with original data on PPH prevalence were included in our systematic review. We calculated the relative risk of PPH in every study as well as an overall relative risk. Four relevant and valid RCTs were found, totalling 11,621 relevant patients. The relative risk of PPH in women treated with MgSO4 is 0.964 (95% CI 0.886 - 1.050) In this systematic review we found no significant increase in PPH in women treated with MgSO4. However, there is still room for discussion due to the heterogeneity in methods (dosage and duration of treatment), results, and tertiary outcomes, as well as the small number of studies found with respect to this important issue.

关键词： Magnesium Sulfate (MgSO4) Postpartum Hemorrhage (PPH)

The influence of prolapse surgery on sexual activity of women

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Open j.urnal of Obstetrics and Gynecology 2014年第3期4卷 158-164页

作者： Linde T. van Genugten Paul j. q. van der Linden Department of Gynaecology and Obstetrics Deventer Hospital Deventer The Netherlands

Aims: A prospective study to assess sexual activity in patients with pelvic organ prolapse (POP) and evaluate changes in sexual functioning after surgery. Secondary outcomes were q.ality of life and anatomical results. Methods: Patients completed the validated Leiden q.estionnaire (Lq. and the short form 36 (SF-36) pre- and two months postoperatively. SPSS 19.0 was used for statistical analysis. Results: 74 patients (average age 61.5 years) were approached, of whom 33.8% were sexually inactive due to other reasons than POP. 23 patients (average age 56.7 years) were included for further analysis. Postoperatively we found a significant improvement for orgasm during intercourse. The remaining domains didn’t change significantly. A trend is noted, indicating that sexual activity stayed unchanged in 82.6% of patients. Dyspareunia improved in 47.8% of patients, lubrication in 34.8% and sexual satisfaction in 40%. q.ality of life improved in 73.9%. We found a significant improvement in POP grading. Conclusion: More than a third of the patients presenting with POP are not sexually active due to other reasons than POP. POP surgery appears to improve lubrication, dyspareunia, sexual satisfaction and orgasm during intercourse in a considerable part of patients. Furthermore, there’s no negative influence on sexual activity. POP surgery improves q.ality of life in the maj.rity of patients.

关键词： Sexual Activity Sexual Functioning Pelvic Organ Prolapse Surgery Leiden q.estionnaire