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Tailor-Made PAMA VII to Optimize Automatic Transmission Fluid Rheological Requirements

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润滑油 2008年第2期23卷 27-32页

作者： alex tsay Bernard Kinker Evonik RohMax Asia-Pacific Pte.Ltd. Evonik RohMax USA

There are three predominant aspects of the rheological requirements: maximum possible high temperature thickening,minimum possible low-temperature thickening,and high shear stability for automatic transmission *** temperature thickening by VI improvers is largely a function of molecular size and high solubility to give extended polymer coil *** the other hand,the desirable characteristic of minimum low-temperature thickening is a function of somewhat the opposite characteristic;namely relatively poor solubility leading to minimal polymer coil size and thus low viscosity *** addition to not thickening fluids at cold temperatures VI improvers should also provide control of wax-gelation which,if unfettered,can lead to congealed *** the third property of high shear stability is in direct conflict with the desirable characteristic of large molecular size for effective high temperature *** this paper we shall attempt to sort out these conflicting properties and provide some insight into how we approach design of VI improvers for the highly demanding world of automatic transmission fluid rheology.

关键词：自动传动液润滑剂稳定性低温流最优化流变学特制

Low-Temperature Performance of Chinese Automotive Engine Oils-Status and Perspectives

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润滑油 2007年第6期22卷 53-60,64页

作者： Theodore Selby Christian Neveu alex tsay Savant Group MidlandMichiganU.S.A. Degussa RohMax France S.A.SParisFrance Degussa China ShanghaiChina

Performance of automotive engine oils at low temperature has been extensively investigated in the last 50 *** resulting understanding of engine oil rheology has been used to devise bench tests that predict their per- formance under cold starting *** starting the engine has been essentially overcome for passenger car en- gines with fuel injection but pumpability of the engine oil has grown more *** tests(MRV TP1 and the Scanning Brookfield Technique with Gelation Index measurement)have become the measures of quality in pumpabili- ty response at low *** such they have become ASTM Methods and are included in a number of interna- tional specifications such as SAE J300 and ILSAC/API GF-1,2,3,and 4 accompanied by appropriate limits. For a number of years,the Institute of Materials(IOM) has generated a database for Asia-Pacific engine oils for IOM *** database can be used to assess and compare the performance of Chinese engine oils at low temperature to one another and to the larger world of engine oils also covered by the IOM *** IOM survey of Asia-Pacific provides a complete 36-test analysis of 300 passenger car engine oils from the region including a wide range of chemical analysis,rheological measurements and performance *** this paper we concen- trate on the low temperature analysis of the rheology of samples collected in China since 2000. The important factors affecting formulation of engine oils in China today are: *** recent inclusion of the MRV TP-1 and Scanning Brookfield Gelation Index requirements in China's National Standards for engine oil quality; *** availability of higher quality oils; *** higher treat rate of additives will require increased attention from the formulators in the selection of VI Improvers and Pour Point Depressants(PPDs). In the latter case,new PPDs are likely to be required to provide formulators with robust and economical solu- tions to face these new challen

关键词：低温条件中国汽车用油倾点

Influence of Polyalkylmethacrylate VII on Boundary Film Formation,Friction,Wear and Efficiency of Lubricants

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润滑油 2006年第6期21卷 46-54页

作者： Michael Müller Hugh Spikes alex tsay Degussa RohMax Additives GmbH DarmstadtGermany Tribology Section Imperial CollegeLondonUK Degussa(China) ShanghaiChina

Polyalkylmethacrylates(PAMAs) are well-known as viscosity index improvers and dispersant *** paper shows that PAMAs are able to adsorb from oil solution on to metal surfaces,to produce thick,viscous boundary *** films enhance lubricant film formation in slow speed and high temperature conditions and thus produce a significant reduction of friction.A systematic study of this phenomenon has made use of the highly flexible nature of PAMA chemistry.A range of dispersant and non-dispersant polymethacrylates has been *** influence of different functionalities,molecular weights and architectures on both boundary film formation and friction has been explored using optical interferometry and friction-speed *** the results, guidelines have been developed for designing PAMAs having optimal boundary lubricating *** their ability to form boundary films PAMAs can significantly contribute to reduce wear in engine,gear and hydraulic *** a consequence of their viscometric and tribological performance PAMAs can furthermore improve fuel and energy efficiency in different,namely engine and hydraulic *** work is currently conducted in the lubricant industry to develop engine oils with lower sulfur,phosphorus and metal content(low SAPS) and to optimize their frictional properties through the use of friction modifiers or synthetic base *** have investigated the contribution of PAMA viscosity index improvers and boosters to improve fuel economy and to reduce wear *** paper reports our efforts to develop a new range of PAMAs that have been optimized in terms of composition,architecture,molecular weight and functionality and which can be used in low viscosity,low SAPS formulations to help meet the stringent requirements of modern engine oils.

关键词：润滑油添加剂耗油量摩檫力胶卷

Performance and Selection of Pour Point Depressants

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润滑油 2005年第5期20卷 26-29页

作者： Christian Neveu Phil Hutchinson alex tsay Nick Gu Degussa-RohMax Oil Additives Degussa-RohMax Oil AdditivesDegussa-RohMax Oil AdditivesDegussa-RohMax Oil Additives

When temperature of paraffinic mineral oil base stocks is decreased belowcloud point,waxy hydrocarbonscome out of solution and growinto plates and needles wax crystalsforming a three-di mensional networkthat totallyi m-mobilizes the *** of a properlyselected PPD will provide a verylarge enhancement of low-temperature perfor-mance of the oil at *** a right PPDfor your formulations are discussedinthis paper.

关键词：润滑油 PPD 温度蜡状物

Quantifying the Efficiency Advantages of High Viscosity Index Hydraulic Fluids

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润滑油 2006年第5期21卷 23-33页

作者： Christian D.Neveu Michael D.Zink alex tsay RohMax France ParisFrance RohMax USA HorshamPAUSA Degussa(China) ShanghaiChina

By providing higher in-use viscosity at elevated operating temperatures,hydraulic fluids with high viscosity index improve the efficiency of the hydraulic *** mobile hydraulic equipment this efficiency can be quantified as an increase in fuel *** paper reviews the research that demonstrates these efficiency advantages in gear,vane and piston pumps and presents a method for predicting the overall fuel economy for a fleet of hydraulic equipment in *** a `Maximum Efficiency Hydraulic Fluid’ performance definition is presented which will enable an equipment operator to easily improve the performance of the system and reduce fuel consumption.

关键词：最高效率液压机液体粘度指数泵效率容积效率

Clinical and socioeconomic determinants of survival in biliary tract adenocarcinomas

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1374-1383页

作者： Laura Sahyoun Kay Chen Cynthia tsay George Chen Petr Protiva Department of Gastroenterology and Hepatology Weill Cornell MedicineNew YorkNY 10065United States Gastroenterology Section Jennifer Moreno VA San Diego Healthcare SystemSan DiegoCA 92161United States Division of Gastroenterology Department of MedicineUniversity of California San DiegoLa JollaCA 92093United States Department of Gastroenterology and Hepatology John Hopkins HospitalBaltimoreMD 21287United States Department of Digestive Diseases Yale New Haven HospitalNew HavenCT 06520United States Department of Gastroenterology VA Connecticut Health Care SystemWest HavenCT 06516United States

BACKGROUND Despite advances in detection and treatments,biliary tract cancers continue to have poor survival ***,there is limited data investigating the significance of socioeconomic status,race/ethnicity,and environmental factors in biliary tract cancer *** from the Surveillance,Epidemiology,and End Results database for biliary and gallbladder adenocarcinomas were extracted from 1975 to ***-conomic data included smoking,poverty level,education,adjusted household income,and percentage of foreign-born persons and urban *** was calculated with Cox proportional hazards models for death in the 5-year period following *** Our study included 15883 gallbladder,11466 intrahepatic biliary,12869 extrahepatic biliary and 7268 ampulla of Vater adenocarcinoma *** analyzing county-specific demographics,patients from counties with higher incomes were associated with higher survival rates[hazard ratio(HR)=0.97,P<0.05].Similarly,counties with a higher percentage of patients with a college level education and counties with a higher urban population had higher 5-year survival rates(HR=0.96,P=0.002 and HR=0.97,P=0.004,respectively).CONCLUSION Worse survival outcomes were observed in lower income counties while higher income and education level were associated with higher 5-year overall survival among gallbladder and biliary malignancies.

关键词： Biliary tract cancers Survival Outcomes research Socioeconomic factors Healthcare disparities

Assessing the Effectiveness of Strategies in US Birth Cohort Screening for Hepatitis C Infection

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Journal of Clinical and Translational Hepatology 2020年第1期8卷 25-41页

作者： Cynthia J.tsay Joseph K.Lim Department of Internal Medicine Yale University School of MedicineNew HavenCTUSA Yale Liver Center Section of Digestive DiseasesYale University School of MedicineNew HavenCTUSA

Chronic hepatitis C infection in the USA is a highly morbid condition and current guidelines recommend one-time screening among the birth cohort(1945-1965).Understand-ing strategies to optimize screening can help inform future hepatitis C virus(HCV)screening guidelines.A focused literature search was performed using PubMed and manual abstract review from major hepatology conferences over the past 2 *** search strategy involved using Medical Subject Headings terms for hepatitis C,screening,birth cohort,baby boomers,and *** review was limited to data from the USA.A total of 327 articles were identified and 36 abstracts were included,with studies published between *** including clinician education,electronic medical record alerts,reflex HCV RNA testing,point-of-care testing,multisite(outpatient,inpatient,emergency department,endoscopy suite)initiatives,direct patient solicitation,and utilization of non-physician providers have increased HCV screening ***,broad imple-mentation remains less than *** include lack of patient acceptance to screening and engagement in the HCV care *** Veterans Affairs Healthcare System has achieved higher birth cohort screening rates through an integrated approach requiring high-level engagement by leadership and institutional *** strategies for increasing birth cohort screening have been successful,but overall rates of HCV screening remain *** strat-egies can inform public health efforts to implement emerging national recommendations for expansion of HCV screening to all *** age 18 or older.

关键词： Hepatitis C Epidemiology HCV antibody Screening Birth cohort Baby boomers Care cascade Electronic medical records

Carbon storage potential of avenue trees:a comparison of Barringtonia racemosa,Cyclobalanopsis glauca,and Alnus formosana

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Journal of Forestry Research 2015年第2期26卷 307-314页

作者： Jyh-Shyan tsay Pei-Hsin Ko Pai-Tsang Chang Department of Horticultural Science National Chiayi University

Trees in cities play a valuable public health role for they are able to use photosynthesis to absorb atmospheric carbon dioxide(CO2),which is then stored as tree *** present study compared the potential for carbon storage in the aboveground tree biomass of 3-year-old specimens of Barringtonia racemosa,Cyclobalanopsis glauca,and Alnus formosana grown in Chiayi City,*** of the carbon storage of avenue trees was based on measurement of the photosynthetic rate and leaf area,as well as the biomass of timbers,from October 2008 to *** on photosynthetic rates and leaf area,the estimated carbon stocks of ***,***,and *** are 756,615,and2738 kg Cha-1a-1,*** addition,carbon storage can be estimated based on timber volume,and these results are 1170,720,and 1995 kg Cha-1a-1for ***,***,and ***,*** on these findings,*** has the highest carbon fixation potential of these three *** the photosynthetic rate measurements can provide detailed data on the diurnal changes in carbon stocks,this requires more time and *** contrast,timber volume measurements provide a rapid and convenient way to estimate carbon stocks.

关键词： Carbon dioxide Carbon stock Greenhouse gas Leaf area Timber volume

Relationships between pain intensity and heart rate variability in patients after abdominal surgery： a pilot study

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Chinese Medical Journal 2012年第11期125卷 1964-1969页

作者： CHANG Ling-hua MA Tso-chiang tsay Shiow-luan JONG Gwo-ping Department of Nursing Landseed Hospital Taoyuan and College of Nursing National Taipei University of Nursing and Health Sciences Taipei Taiwan China Department of Health Service Management China Medical University Taichung Taiwan China College of Nursing National Taipei University of Nursing and Health Sciences Taipei Taiwan China Division of Internal Cardiology Taichung Armed Forces General Hospital and Central Taiwan University of Science and Technology Taichung 41168 Taiwan China

Background A link between postoperative pain intensity and heart rate variability （HRV） had not been well established. This study aimed to investigate the correlation between post-operative pain intensity and HRV. Methods The subjects in this cross-sectional correlation study comprised of patients who had undergone abdominal surgery in a regional teaching hospital in central Taiwan during the period July 2009-November 2009. The visual analogue scale （VAS） and the short-form McGill pain questionnaire （SF-MPQ） were used to measure post-operative pain. HRV was measured as the standard deviation of normal RR interval, and by power spectral analysis that included high frequency （HF）, low frequency （LF）, very low frequency power, and LF/HF ratio. Results A total of 34 subjects were included in this study. We found that the day after the surgery, the mean VAS score was 47.50±20.98 and the mean SF-MPQ score was 18.06±8.90, indicating a moderate degree of pain. Moderate to severe degrees of tenderness were reported by 70.6% of the patients, moderate to severe degrees of gnawing pain were experienced by 67.7% of the patients, moderate to severe degrees of tiring-exhaustion pain were reported by 64.7% of the patients, and 41.2% of the patients who experienced moderate to severe pain believed that the pain was punishing-cruel. The standard deviation of normal RR interval and high frequency values obtained from male patients or married patients were higher than female patients or unmarried （P 〈0.05）. The correlation of the standard deviation of normal RR interval, high frequency, very low frequency value and patient＇s age were negative （P 〈0.05）. The total SF-MPQ pain scores positively correlated with the LF/HF ratio （P 〈0.05）. Conclusions The multidimensional pain assessment tool （SF-MPQ） reflects better the patients＇ post-operative pain than the single-dimensional assessment tool （VAS）. HRV positively correlated with SF-MPQ scores in patients after abdominal surgery.

关键词： heart rate variability postoperative pain abdominal surgery short-form McGill pain questionnaire