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| 1 | 硅烷改性混凝土防水和抗氯离子性能试验研究显示文摘通过中子成像试验、吸水试验和氯离子侵蚀试验,研究无裂缝和带裂缝情况下硅烷改性混凝土的防水和抗氯离子侵蚀性能。试验结果表明,中子成像能够清晰观测未掺硅烷试件的快速吸水过程,而掺加硅烷后在毛细孔隙壁上形成的憎水膜能够有效抑制液态水分侵入,中子成像观测不到肉眼可见的水分前锋,吸水量降为未掺硅烷时的13%,显示出良好的防水性能。硅烷在水泥基体中的水解缩合反应并不堵塞毛细孔隙,保持'可呼吸性'。未改性试件一旦开裂,水在瞬间充满裂缝继而向裂缝两侧入侵,而硅烷改性试件即使开裂宽度达0.3mm,也无明显水分运动,裂缝在0.1mm~0.4mm扩展时不削弱其整体防水效果。良好的防水性能决定了硅烷改性混凝土无论是在无裂缝还是带裂缝情况下都具有良好的抗氯离子侵蚀能力。掺加硅烷改性是提高混凝土材料防水和抗氯离子侵蚀能力,进而提高其耐久性的有效途径。 | 张鹏 赵铁军 戴建国 郭平功 Wittmann F H | 2011 | 土木工程学报2011，44，3： | 37 |
| 2 | 冻融和碳化作用对混凝土氯离子侵蚀的影响显示文摘对4种不同配比混凝土先后进行冻融循环(0,50,150次)、加速碳化(0,1,2星期)和氯离子侵蚀,以研究冻融、碳化作用对混凝土氯离子侵蚀的影响.通过压汞法和选择电极法分别测定不同作用后混凝土的孔径分布和氯离子含量及其毛细吸收变化情况.结果表明:冻融循环增大混凝土孔隙率,作为混凝土损伤的动力源,为氯离子侵蚀创造更为有利的条件;冻融次数越多,造成的氯离子侵蚀越严重;碳化反应破坏混凝土基体原有的过滤机制,并促进Friedel盐分解,使氯离子含量增多;冻融与碳化均不同程度增大混凝土毛细吸水性能,两者共同作用较单独作用时的氯离子侵蚀严重得多.对混凝土结构进行耐久性设计和使用寿命预测时,必须考虑和引进冻融、碳化及其他因素的复合作用. | 张鹏 赵铁军 郭平功 Wittmann Folker H | 2006 | 东南大学学报(自然科学版)2006，36，S2： | 27 |
| 3 | 基于中子成像的水泥基材料毛细吸水动力学研究显示文摘总结了国内外有关水泥基材料毛细吸水的动力学机理及其现有模型,应用中子成像技术对其毛细吸水过程进行了可视化再现,对水分侵入的空间分布规律进行了定量分析。结果表明,在毛细孔吸附力作用下,水分前锋不断向水泥基材料内部推进,在吸水初期速度较快,后趋于平缓直至稳定;水分侵入曲线在深度和含量上同时增长,可以由线性+反S形模型来描述其空间分布特点,并与实测结果吻合良好;现有的'时间开方'及其修正模型对毛细吸水的后期预测不太合理,本文提出的渗透系数双曲线衰减模型更符合真实结果。 | 张鹏 赵铁军 Wittmann F.H. Lehmann E. | 2011 | 水利学报2011，42，1： | 17 |
| 4 | Role of antispasmodics in the treatment of irritable bowel syndrome显示文摘Irritable bowel syndrome(IBS)is a long-lasting,relapsing disorder characterized by abdominal pain/discomfort and altered bowel habits.Intestinal motility impairment and visceral hypersensitivity are the key factors among its multifactorial pathogenesis,both of which require effective treatment.Voltage-gated calcium channels mediate smooth muscle contraction and endocrine secretion and play important roles in neuronal transmission.Antispasmodics are a group of drugs that have been used in the treatment of IBS for decades.Alverine citrate,a spasmolytic,decreases the sensitivity of smooth muscle contractile proteins to calcium,and it is a selective 5-HT1A receptor antagonist.Alverine,in combination with simethicone,has been demonstrated to effectively reduce abdominal pain and discomfort in a large placebo-controlled trial.Mebeverine is a musculotropic agent that potently blocks intestinal peristalsis.Non-placebo-controlled trials have shown positive effects of mebeverine in IBS regarding symptom control;nevertheless,in recent placebo-controlled studies,mebeverine did not exhibit superiority over placebo.Otilonium bromide is poorly absorbed from the GI tract,where it acts locally as an L-type calcium channel blocker,an antimuscarinic and a tachykinin NK2receptor antagonist.Otilonium has effectively reduced pain and improved defecation alterations in placebocontrolled trials in IBS patients.Pinaverium bromide is also an L-type calcium channel blocker that acts locally in the GI tract.Pinaverium improves motility disorders and consequently reduces stool problems in IBS patients.Phloroglucinol and trimethylphloroglucinol are non-specific antispasmodics that reduced pain in IBS patients in a placebo-controlled trial.Antispasmodics have excellent safety profiles.T-type calcium channel blockers can abolish visceral hypersensitivity in animal models,which makes them potential candidates for the development of novel therapeutic agents in the treatment of IBS. | Anita Annaházi Richárd Róka András Rosztóczy Tibor Wittmann | 2014 | World Journal of Gastroenterology2014，20，20： | 15 |
| 5 | 冻融前后混凝土碳化性能试验研究显示文摘通过对四种不同配合比的混凝土先后进行冻融循环试验(0、50、150次)和加速碳化试验(0、1、2周),研究冻融前后混凝土碳化性能变化情况。结果表明:冻融循环增大了混凝土孔隙率,加速了碳化进程,循环次数越多,加速作用越大;在冻融和高浓度CO2环境下,粉煤灰的掺入增加了混凝土碳化量,并造成较大强度损失,对混凝土结构不利;碳化使混凝土抗压强度略有提高,但不足以弥补冻融造成的强度损失,水灰比越大,强度损失越大。对混凝土结构进行耐久性设计和使用寿命预测时,必须考虑冻融、碳化及其它因素的复合作用。 | 张鹏 赵铁军 杨进波 Wittmann Folker H | 2007 | 混凝土2007，，5： | 14 |
| 6 | 内掺烷基烷氧基硅烷乳液制备整体防水混凝土显示文摘用内掺烷基烷氧基硅烷乳液制备了整体防水混凝土,通过强度、吸水系数和氯离子侵入等试验对其性能进行了研究。结果表明,硅烷乳液延缓了水泥水化反应,使混凝土强度降低,掺量不宜超过3%;内掺硅烷能够降低混凝土的吸水系数88%以上,即使表面磨损7mm,降低率仍保持在82%以上,体现了其整体防水性;由于混凝土中部分微小凝胶孔的孔壁不能被憎水化,决定了硅烷掺量存在一个临界值,为3%;此外,防水混凝土能有效抑制氯离子侵入,使氯离子渗透深度由12mm降为4~6mm。 | 张鹏 赵铁军 金祖权 Wittmann F.H | 2009 | 新型建筑材料2009，36，3： | 13 |
| 7 | Association between autoimmune pancreatitis and systemic autoimmune diseases显示文摘AIM: To investigate the association between autoimmune pancreatitis (AIP) and systemic autoimmune diseases (SAIDs) by measurement of serum immunoglobulin G4 (IgG4). METHODS: The serum level of IgG4 was measured in 61 patients with SAIDs of different types who had not yet participated in glucocorticosteroid treatment. Patients with an elevated IgG4 level were examined by abdominal ultrasonography (US) and, in some cases, by computer tomography (CT). RESULTS: Elevated serum IgG4 levels (919 ± 996 mg/L) were detected in 17 (28%) of the 61 SAID patients. 10 patients had Sj gren's syndrome (SS) (IgG4: 590 ± 232 mg/L), 2 of them in association with Hashimoto's thyroiditis, and 7 patients (IgG4: 1388 ± 985.5 mg/L) had systemic lupus erythematosus (SLE). The IgG4 level in the SLE patients and that in patients with SS were not significantly different from that in AIP patients (783 ± 522 mg/L). Abdominal US and CT did not reveal any characteristic features of AIP among the SAID patients with an elevated IgG4 level. CONCLUSION: The serum IgG4 level may be elevated in SAIDs without the presence of AIP. The determination of serum IgG4 does not seem to be suitable for the differentiation between IgG4-related diseases and SAIDs. | Viktória Terzin Imre Fldesi László Kovács Gyula Pokorny Tibor Wittmann László Czakó | 2012 | World Journal of Gastroenterology2012，18，21： | 9 |
| 8 | 海水环境下混凝土的断裂能及其应变软化显示文摘通过带切口梁的三点弯曲试验和楔形劈拉试验,对完全干燥、半干燥、水浸泡、海水浸泡和5%、23.4%NaCl溶液浸泡的6种不同含水状态的混凝土试件进行了测试,根据荷载-位移曲线和逆向分析,计算得到混凝土的断裂能及其应变软化曲线。结果表明,随着混凝土中水、海水和高浓度盐溶液的侵入,孔隙溶液中液体的表面张力不断增大,造成表面能下降,承载力随之降低,水浸泡后混凝土的最大承载力较干燥时降低19.6%(三点弯曲)和14.5%(楔形劈拉),海水浸泡后下降28.9%和21.7%,高浓度盐溶液浸泡后降幅更大;海水和盐溶液浸泡时后,混凝土断裂能损失24%以上,软化阶段的开裂韧性也明显降低,裂缝更易形成和扩展。从表面能、断裂能和应变软化的角度研究了海水侵入对混凝土材料造成的不利影响。 | 张鹏 孙志伟 赵铁军 Wittmann F H | 2010 | 土木建筑与环境工程2010，，1： | 9 |
| 9 | 开裂混凝土中水分侵入过程的可视化追踪及其特征分析显示文摘采用热中子辐射成像技术,对开裂混凝土中的水分侵入过程进行了试验研究与特征分析。结果表明:中子成像能够突破混凝土材料的非透明性局限,实现对开裂混凝土中水分侵入过程的可视化追踪和水分空间分布的定量计算;水分在开裂混凝土中不仅由与水初始接触面沿垂直方向推进,而且还沿裂缝两侧向其水平方向,以及钢筋与水泥基体界面外围方向同时入侵;裂缝区和钢筋与水泥基体界面区成为水分持续侵入的二次水源;水分侵入初期约2h内,根据试验中裂缝宽度为0.35mm试件的中子图像估算的水分侵入量与称量法测得的水分侵入量基本一致。 | 张鹏 赵铁军 WITTMANN F H LEHMANN E 金祖权 VONTOBEL P | 2010 | 硅酸盐学报2010，38，4： | 8 |
| 10 | 混凝土冻融损伤后的吸水特性显示文摘对掺与未掺引气剂的混凝土进行了冻融破坏,通过吸水试验和中子辐射试验,研究了冻融损伤对掺与未掺引气剂混凝土吸水特性的影响.结果表明,中子成像技术能够实现对非透明性混凝土材料吸水演进过程的可视化观测和定量分析.未掺引气剂的混凝土其抗冻性较差,在10次冻融循环后动弹模量损失14%的情况下,其水分渗透深度约增30%;掺加引气剂后,即使遭受200次冻融循环,混凝土的整体动弹模量也无明显损失,但200次冻融循环后,混凝土表层出现部分剥落,水分渗透速率及深度均相应增大.在评价混凝土冻融损伤时,除整体动弹模量损失外,还需考虑冻融损伤对混凝土吸水性能的影响. | 张鹏 张连水 赵铁军 F. H. WITTMANN E. LEHMANN 金祖权 | 2011 | 建筑材料学报2011，14，2： | 7 |
| 11 | 高韧性PVA-SHCC多缝开裂后吸水特性研究显示文摘制备了高韧性PVA-SHCC(聚乙烯醇-应变硬化水泥基复合材料)试件,通过吸水试验和中子成像试验,研究了未开裂和直拉多缝开裂情况下SHCC的吸水特性.结果表明:中子成像能够对无裂缝和多缝开裂SHCC试件的吸水过程进行可视化追踪和定量分析计算;SHCC在无裂缝时吸水很少,中子成像无肉眼可见的水分前锋;多缝开裂后,能够清晰探测到水分沿80~140μm的裂缝迅速侵入材料内部,并通过遭横向拉拔破坏的纤维与水泥基体界面而充满裂缝区;在这种情况下,应从耐久性角度限制SHCC多重裂缝宽度. | 张鹏 F. H. WITTMANN 赵铁军 E.LEHMANN 田砾 | 2011 | 建筑材料学报2011，14，3： | 7 |
| 12 | Chloride content and pH value in the pore solution of concrete under carbonation显示文摘Chloride content and the pH value of the pore solution in the neighborhood of steel reinforcement are decisive parameters for initiation and rate of corrosion. The pore solution of cement mortar and hardened cement paste has been expressed from the pore space by high pressure in the investigation. The influence of the water-cement ratio, age, and addition of chloride to the fresh mix on chloride content in the pore solution has been determined by ion chromatography. At the same time the pH value of the pore solution has been determined. The dissolved chloride content decreases with increase in the water-cement ratio. The amount of bound chloride increases with time, but it decreases with decreasing content of dissolved chloride in the pore solution. A significant influence of carbonation on the dissolved chloride content of the pore solution has been observed. With complete carbonation, the dissolved chloride content in cement mortar and hardened cement paste increases by a factor between 2 and 12. The bound chloride decreases by 27%-4%. As expected, the pH value decreases from around 13.2 to as low as 8.0 due to carbonation. It can be concluded that carbonation not only lowers the pH value but liberates bound chloride. This is one obvious reason why the combined action of chloride penetration and carbonation accelerates steel corrosion and shortens the service life of reinforced concrete structures. | Xiao-mei WAN Folker H. WITTMANN Tie-jun ZHAO Hong FAN | 2013 | Journal of Zhejiang University-Science A(Applied Physics & Engineering)2013，14，1： | 6 |
| 13 | 复碱化混凝土孔溶液的pH值(英文)显示文摘碳化混凝土的复碱化是用碳酸钙缓冲溶液浸渍混凝土的电化学过程,目的是使混凝土孔溶液的pH值稳定在10以上,从而防止混凝土的进一步碳化.然而,该方法的实际应用表明:虽然孔溶液中已明显含有足量的碱(Na+,K+,Li+),但pH值仍降到10以下.本文通过试验提出了一个用以解释pH值随时间降低的假说,结果表明:由于混凝土孔溶液中存在溶解的硫酸盐,因此单纯提高孔溶液的碱离子(碳酸盐)相对含量,不能确保其pH值高于10.用提出的化学机理可解释混凝土电化学复碱化技术实际应用中观察到的现象,但是,由于混凝土孔溶液中溶解离子相互作用十分复杂,目前还不能在复碱化技术中对其加以考虑,因此复碱化技术尚不能被进一步推荐应用. | A. Gerdes F. H. Wittmann | 2003 | 建筑材料学报2003，6，2： | 6 |
| 14 | 基于反向分析计算水泥基体的湿扩散系数显示文摘在总结国内外有关湿扩散非线性模型的基础上,提出了一种反向分析计算水泥基体湿扩散系数的方法,并采用进化算法对迭代计算过程进行了优化。将初始湿度为95%的3组同样试件分别置于76%、60%和47%的环境湿度下进行湿扩散试验,确定所需的材料参数以及初始和边界条件后,分别对3组试验数据进行独立计算,得到了基本相同的湿扩散系数,失水量的计算值与实测值也几乎吻合,表明该方法具有良好的可行性和满意度。 | 张鹏 赵铁军 Wittmann F.H. Slowik V. | 2010 | 水利学报2010，40，1： | 6 |
| 15 | Visualization and quantification of water movement in porous cement-based materials by real time thermal neutron radiography:Theoretical analysis and experimental study显示文摘Water movement in porous cement-based materials is of great importance when studying their deterioration processes and durability.Many traditional methods based on mass changes,electricity or nuclear magnetic resonances are available for studying water transport in cement-based materials.In this research,an advanced technique i.e.thermal neutron radiography was utilized to achieve visualization and quantification of time dependent water movement including water penetration and moisture vapor in porous cement-based materials through theoretical analysis and experimental study.Because thermal neutrons ex-perience a strong attenuation by hydrogen,neutron radiography exhibits high sensitivity to small amounts of water.A neutron transmission analysis for quantitative evaluation of raw radiographic measurements was developed and optimized based on point scattered functions(PScF).The determinations of the real time and space dependent water penetration into uncracked and cracked mortar samples,as well as the drying process have been presented in this paper.It is illustrated that thermal neutron radiography can be a useful research tool for visualization and quantification of water movement in porous building materials.The obtained results will help us to better understand deteriorating processes of cement-based materials and to find ways to improve their durability. | ZHANG Peng1,WITTMANN F H1,2,ZHAO TieJun1,LEHMANN E3 & JIN ZuQuan1 1 Center for Durability & Sustainability Studies of Shandong Province,Qingdao Technological University,Qingdao 266033,China 2 Aedificat Institute Freiburg,Freiburg D-79100,Germany 3 Department of Spallation Neutron Source(ASQ),Paul Scherrer Institute,Villigen PSI CH-5232,Switzerland | 2010 | Science China(Technological Sciences)2010，53，5： | 6 |
| 16 | The natural history of Ebola virus in Africa显示文摘 | Xavier Pourrut Brice Kumulungui Tatiana Wittmann Ghislain Moussavou André Délicat Philippe Yaba Dieudonné Nkoghe Jean-Paul Gonzalez Eric Maurice Leroy | 2005 | Microbes and Infection2005，，7： | 4 |
| 17 | Antecedents and consequences of opportunism in buyer–supplier relations: Research synthesis and new frontiers显示文摘 | Timothy G. Hawkins C. Michael Wittmann Michael M. Beyerlein | 2007 | Industrial Marketing Management2007，，8： | 3 |
| 18 | Synchronous electrogastrographic and manometric study of the stomach as an esophageal substitute显示文摘AIM: To investigate the electric and contractile mechanisms involved in the deranged function of the transposed stomach in relation to the course of the symptoms and the changes in contractile and electrical parameters over time.METHODS: Twenty-one patients after subtotal esophagectomy and 18 healthy volunteers were studied.Complaints were compiled by using a questionnaire, and a symptom score was formed. Synchronous electrogastrography and gastric manometry were performed in the fasting state and postprandially.RESULTS: Eight of the operated patients were symptomfree and 13 had symptoms. The durations of the postoperative periods for the symptomatic (9.1±6.5 mo)and the asymptomatic (28.3±8.8 mo) patients were significantly different. The symptom score correlated negatively with the time that had elapsed since the operation. The percentages of the dominant frequency in the normogastric, bradygastric and tachygastric ranges differed significantly between the controls and the patients.A significant difference was detected between the power ratio of the controls and that of the patients. The occurrence of tachygastria in the symptomatic and the symptom-free patients correlated negatively both with the time that had elapsed and with the symptom score. There was a significant increase in motility index after feeding in the controls, but not in the patients. The contractile activity of the stomach increased both in the controls and in the symptom-free patients. In contrast, in the group of symptomatic patients, the contractile activity decreased postprandially as compared with the fasting state.CONCLUSION: The patients' post-operative complaints and symptoms change during the post-operative period and correlate with the parameters of the myoelectric and contractile activities of the stomach. Tachygastria seems to be the major pathogenetic factor involved in the contractile dysfunction. | Ferenc Izbéki Tibor Wittmann Sándor (O|')dor Balázs Botos (A|')ron Altorjay | 2005 | World Journal of Gastroenterology2005，11，8： | 2 |
| 19 | Elevated miR-33a and miR-224 in steatotic chronic hepatitis Cliver biopsies显示文摘AIM:To assess the expression of selected microRNAs(miRNA) in hepatitis C,steatotic hepatitis C,noninfected steatotic and normal liver tissues.METHODS:The relative expression levels of miR-21,miR-33 a,miR-96,miR-122,miR-125 b,miR-221 and miR-224 were determined in 76 RNA samples isolated from 18 non-steatotic and 28 steatotic chronic hepatitis C(CHC and CHC-Steatosis,respectively) cases,18 non-infected,steatotic liver biopsies of metabolic origin(Steatosis) and 12 normal formalin-fixed paraffin-embedded liver tissues using TaqMan MicroRNA Assays.All CHC biopsy samples were obtained prior to initiating therapy.Patients' serum biochemical values,which included glucose,triglyceride,cholesterol,alanine aminotransferase(ALT),aspartate aminotransferase(AST),gamma-glutamyl-transferase(GGT),alkaline phosphatase(AP),were obtained and correlated with relative miRNA expression.RESULTS:When compared with control non-infected liver samples,miR-122 and miR-221 levels were reduced in CHC-Steatosis(P < 0.03) and in CHC,CHCSteatosis and Steatosis(P < 0.01).Alternatively,the expression of miR-33 a and miR-224 were elevated in CHC-Steatosis and Steatosis in comparison to control tissue(P < 0.01).The levels of miR-33 a and miR-224 in CHC-Steatosis(P < 0.02) and miR-224 in Steatosis(P < 0.001) were increased in comparison to CHC samples.By contrast,the expression of miR-21 did not differ statistically between diseased and normal liver samples.Levels of miR-33 a correlated negatively with serum AST and AP levels in Steatosis as well as with necroinflammatory grade in CHC,whereas miR-21 correlated positively with AST in Steatosis and displayed negative correlation with triglyceride level in CHC-Steatosis.In contrast,miRNA levels were not correlated with ALT,GGT,cholesterol levels or fibrosis stage.CONCLUSION:Differences in miRNA expression were observed between CHC and steatotic CHC,CHC and steatotic liver,but not between steatotic CHC and steatotic liver of metabolic origin. | Gabor Lendvai Katalin Jármay Gizella Karácsony Tünde Halász Ilona Kovalszky Kornélia Baghy Tibor Wittmann Zsuzsa Schaff András Kiss | 2014 | World Journal of Gastroenterology2014，20，41： | 2 |
| 20 | Frequency and prognostic role of mucosal healing in patients with Crohn's disease and ulcerative colitis after one-year of biological therapy显示文摘AIM:To assess the endoscopic activity before and after a one-year period of biological therapy and to evaluate the frequency of relapses and need for retreatment after stopping the biologicals in patients with Crohn’s disease(CD)and ulcerative colitis(UC).METHODS:The data from 41 patients with CD and 22 patients with UC were assessed.Twenty-four CD patients received infliximab,and 17 received adalimumab.The endoscopic severity of CD was quantified with the simplified endoscopic activity score for Crohn’s disease in CD and with the Mayo endoscopic subscore in UC.RESULTS:Mucosal healing was achieved in 23 CD and7 UC patients.Biological therapy had to be restarted in78%of patients achieving complete mucosal healing with CD and in 100%of patients with UC.Neither clinical remission nor mucosal healing was associated with the time to restarting the biological therapy in either CD or UC.CONCLUSION:Mucosal healing did not predict sustained clinical remission in patients in whom the biological therapies had been stopped. | Klaudia Farkas Péter László Lakatos Mónika Szcs va Pallagi-Kunstár Anita Bálint Ferenc Nagy Zoltán Szepes Noémi Vass Lajos S Kiss Tibor Wittmann Tamás Molnár | 2014 | World Journal of Gastroenterology2014，20，11： | 2 |
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