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KNO_(3)介稳区宽度的研究及初级成核动力学计算

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无机盐工业 2024年第9期56卷 67-74页

作者：邹洋陆志艳胡志林孙泽华东理工大学资源与环境工程学院上海200237 上海锅炉厂有限公司上海200245 青海民族大学青海西宁810007

为研究KNO_(3)在KNO_(3)-NaNO_(3)-H_(2)O中的冷却结晶过程,采用静态平衡法测量293.15~341.38 K下KNO_(3)在该体系中的溶解度,通过Apelblat方程和Van’t hoff方程得到了溶解度与温度的关系,并计算了KNO_(3)的溶解焓和溶解熵。采用超声... 详细信息

为研究KNO_(3)在KNO_(3)-NaNO_(3)-H_(2)O中的冷却结晶过程,采用静态平衡法测量293.15~341.38 K下KNO_(3)在该体系中的溶解度,通过Apelblat方程和Van’t hoff方程得到了溶解度与温度的关系,并计算了KNO_(3)的溶解焓和溶解熵。采用超声波法研究了298.03~332.30 K下NaNO_(3)含量、搅拌速率和冷却速率对KNO_(3)介稳区宽度的影响。实验结果表明,当体系中存在NaNO_(3)时介稳区宽度变窄但影响有限。KNO_(3)介稳区宽度随搅拌速率的增加而变窄,随冷却速率增加而变宽。以KNO_(3)溶解度和溶解焓数据为基础,研究了KNO_(3)的初级成核动力学,采用自洽Nývlt型方程得到成核级数m小于3,KNO_(3)为瞬时成核,且随着饱和温度的升高,成核速率呈先增大后减小的趋势;在经典三维成核理论中,随着饱和温度的升高,成核更容易发生,当饱和温度达到一定程度后,固-液界面能γ趋于稳定。以农用硝酸钾为原料,通过冷却结晶得到高纯度KNO_(3)产品,当饱和KNO_(3)溶液由343.15 K降至298.15 K、搅拌速率为300 r/min、冷却速率为25 K/h时,添加晶种后,溶液中Na^(+)含量仅为0.0011%。

关键词：硝酸钾硝酸钠介稳区成核动力学工业结晶

Different standards for healthy screenees than patients in routine clinics?

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World Journal of Gastroenterology 2013年第46期19卷 8527-8530页

作者： Geir hoff Department of Research and Development Telemark Hospital Cancer Registry of Norway Institute of Health and Society University of Oslo

Less than 5%of colorectal adenomas will become malignant,but we do not have sufficient knowledge about their natural course to target removal of these5%***,95%of polypectomies are a waste of time exposing patients to a small risk of ***,a new type of polyps,sessile serrated polyps,has attracted *** considered innocuous,they are now found to have molecular similarities to cancer and some guidelines recommend to have them *** lesions are often flat,covered by mucous,not easily seen and situated in the proximal colon where the bowel wall is ***,polypectomy carries a higher risk of perforation than predominantly left-sided,stalked adenomas-and we do not know what is gained in terms of cancer *** is a neat balance between harms and benefit for presumptively healthy participants not interested in risk exposure to obtain confirmation of being *** situation is quite different for patient worried about ***,the standards set for evidence-based practice may be higher for screening than for routine clinics-a mechanism which may benefit patients in the long run.

关键词： Colonoscopy Screening Quality assurance Standards

Storm in the Air： The Battle Over the 1992 Cable Act

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History Research 2016年第3期6卷 121-133页

作者： Samuel B. hoff Delaware State University USA

Utilizing primary documents available at the George Bush Presidential Library, this study evaluates the veto record of President Bush using a case study as well as quantitative methods. The case study reviews the background and fate of the only veto overridden during his term in office. It finds that the Bush White House had tried on several previous occasions to scrap the legislation, only to have it be reintroduced in each succeeding Congress. By 1992, when George Bush was running for reelection and in trouble politically, his team was unable to stave off defeat. The article likewise assesses the success of the Bush administration in its employment of the veto and compares the veto record of President Bush to previous and subsequent chief executives.

关键词： Veto override president Congress cable regulation 1992 Cable Act

Gitmo＇s Folly II： Torture, Trials, and Tribulations of US Detention Policy in the Wake of 9/11

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International Relations and Diplomacy 2016年第7期4卷 454-464页

作者： Samuel B. hoff Delaware State University Delaware USA

Tapping declassified US Senate and Central Intelligence Agency reports, United Nations studies, and other primary sources, this study investigates the etiology, policies, and consequences of US detention policy as a part of the War on Terror. The record of the last two presidential administrations in dealing with detainees at Guantanamo Bay Naval Base in Cuba （GITMO） and elsewhere is examined and the legal rationale for the tactics used on those in captivity is scrutinized. The study reveals that although certain features of detention policy changed from the George W. Bush administration to the Barack Obama presidency, others remained the same. The benefits of information acquired from detainees is weighed and detention policy itself is evaluated according to fundamental American values.

关键词： 9/11 Guantanamo Bay Naval Base in Cuba (GITMO) torture detainees

Psychological effects of colorectal cancer screening: Participants vs individuals not invited

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World Journal of Gastroenterology 2016年第43期22卷 9631-9641页

作者： Benedicte Kirk?en Paula Berstad Edoardo Botteri Linn Bernklev Badboni El-Safadi Geir hoff Thomas de Lange Tomm Bernklev Department of bowel cancer screening Cancer Registry of Norway Institute of Clinical Medicine University of Oslo Department of Internal Medicine Vestre Viken Hospital Trust B?rum Hospital Department of Gastroenterology ?stfold Hospital Trust Department of Research and Development Telemark Hospital Trust Department of Health Management and Health Economics Institute of Health and Society University of Oslo

AIM To investigate the possible long-term psychological harm of participating in colorectal cancer(CRC)screening in *** In a prospective, randomized trial, 14294 participants(aged 50-74 years) were invited to either flexible sigmoidoscopy(FS) screening, or a faecal immunochemical test(FIT)(1:1). In total, 4422 screening participants(32%) completed the questionnaire, which consisted of the Hospital Anxiety and Depression Scale and the SF-12, a generic health-related quality of life(HRQOL) measurement, when invited to screening and one year after the invitation. A control group of 7650 individuals was invited to complete the questionnaire only, at baseline and one year after, and 1911(25%) completed the *** Receiving a positive or negative screening result and participating in the two different screening modalities did not cause clinically relevant mean changes in anxiety, depression or HRQOL after one year. FS screening, but not FIT, was associated with an increased probability of being an anxiety case(score ≥ 8) at the one-year follow-up(5.6% of FS participants transitioned from being not anxious to anxious, while 3.0% experienced the reverse). This increase was moderately significantly different from the changes in the control group(in which the corresponding numbers were 4.8% and 4.5%, respectively), P = 0.06. CONCluSION Most individuals do not experience psychological effects of CRC screening participation after one year, while FS participation is associated with increased anxiety for a smaller group.

关键词： Colorectal cancer screening Flexible sigmoidoscopy Fecal immunochemical test Anxiety Health-related quality of life Control group

凝结相中功能性碳材料和碳纳米复合物催化转化生物质制备可再生化学品(英文)

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催化学报 2014年第6期35卷 842-855页

作者： John Matthiesen Thomas hoff Chi Liu Charles Pueschel Radhika Rao Jean-Philippe Tessonnier Department of Chemical & Biological Engineering Iowa State University Ames IA 50011 USA US Department of Energy Ames Laboratory Ames IA 50011 USA NSF-ERC Center for Biorenewable Chemicals (CBiRC) Ames IA 50011 USA

The production of chemicals from lignocellulosic biomass provides opportunities to synthesize chemicals with new functionalities and grow a more sustainable chemical industry. However, new challenges emerge as research transitions from petrochemistry to biorenewable chemistry. Compared to petrochemisty, the selective conversion of biomass-derived carbohydrates requires most catalytic reactions to take place at low temperatures (< 300 °C) and in the condensed phase to prevent reactants and products from degrading. The stability of heterogeneous catalysts in liquid water above the normal boiling point represents one of the major challenges to overcome. Herein, we review some of the latest advances in the field with an emphasis on the role of carbon materials and carbon nanohybrids in addressing this challenge.

关键词：生物质转化碳水化合物纳米复合物催化反应化学物可再生凝聚相功能化学品

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智能聚合物在医药与生物工程中的应用

高分子通报 1995年第4期 245-253页

作者： hoff.,AS 罗毅北京大学化学系

智能聚合物是一类对于外界环境微小的物理和化学刺激，其自身性质会发生明显改变的聚合物。这类聚合物能以各种形式存在，如固体、溶液或吸附于载体表面。水溶性智能聚合物系统与生物分子相结合能够产生一类对物理、化学和生物刺激有响... 详细信息

智能聚合物是一类对于外界环境微小的物理和化学刺激，其自身性质会发生明显改变的聚合物。这类聚合物能以各种形式存在，如固体、溶液或吸附于载体表面。水溶性智能聚合物系统与生物分子相结合能够产生一类对物理、化学和生物刺激有响应的新的聚合物。本文综述了这类聚合物系统的研究进展。

关键词：智能聚合物医药工程生物工程应用聚合物

COX-2 polymorphisms-765G→C and-1195A→G and colorectal cancer risk

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World Journal of Gastroenterology 2009年第36期15卷 4561-4565页

作者： Juliёt H hoff Rene HM te Morsche Hennie MJ Roelofs Elise MJ van der Logt Fokko M Nagengast Wilbert HM Peters Department of Gastroenterology Radboud University Nijmegen Medical Center6500 HB NijmegenThe Netherlands

AIM： TO determine the possible modulating effect of the COX-2 polymorphisms, -765G→C and -1195A→G, on the risk of colorectal cancer （CRC） in a Dutch population. METHODS： This case-control study includes 326 patients with CRC and 369 age- and gender-matched controls. Genotypes of the COX-2 polymorphisms -7dEG→C and -1195A→G were determined by polymerase chain reaction-based restriction fragment length polymorphism. COX-2 genotypes and haplotypes were analyzed and odds ratios with 95% confidence intervals were estimated by logistic regression. RESULTS： The -765GG genotype was associated with an increased risk of developing CRC （OR, 1.45; 95% CI, 1.03-2.04）. No significant difference was observed in the genotype distribution of the -1195A→G polymorphism between patients and controls. The GG/AC haplotype was present significantly less often in patients than in controls （OR 0.44; 95% CI, 0.22-0.85）. When the AC, AG and GG haplotypes were investigated separately, the AC haplotype showed a tendency to be less frequent in patients than in controls （OR（AG/AC） 0.78; 95% CI, 0.57-1.06）. CONCluSION： The -765GG genotype is associated with an increased risk of developing CRC and the G6/ AC haplotype seems to protect against CRC. These findings suggest a modulating role for the COX-2 polymorphisms -765G→C and -1195A→G in the development of CRC in a Dutch population.

关键词： Colorectal carcinoma Cyclooxygenase-2 Genetic polymorphism

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独特的快速更换型夹具

组合机床与自动化加工技术 1997年第4期 30-31页

作者： hoff.,EG 袁扬

独特的快速更换型夹具Ｊｅｒｇｅｎｓ公司ＥｄｗａｒｄＧ．Ｈｏｆｍａｎ主题词：快换夹具精确定位钢球自锁今天，每一个用户都在追求越来越高的加工速度，尽管其很重要，但加工速度只是整个生产过程的一部分，提高生产率必须考虑生产过... 详细信息

独特的快速更换型夹具Ｊｅｒｇｅｎｓ公司ＥｄｗａｒｄＧ．Ｈｏｆｍａｎ主题词：快换夹具精确定位钢球自锁今天，每一个用户都在追求越来越高的加工速度，尽管其很重要，但加工速度只是整个生产过程的一部分，提高生产率必须考虑生产过程中的每一个环节，而不仅仅是提高机...

关键词：快换夹具定位精度夹具