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超高强混凝土中各组分与聚羧酸系超塑化剂之间的相互作用(英文)

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硅酸盐学报 2010年第9期38卷 1605-1612页

作者： SCHROFL C gruber M pLANK j Technische Universitat Munchen Chair for Construction Chemicals Garching LichtenbergstraBe 4 85747 Germany

超高强混凝土(ultra-high strength concrete,UHSC)的水灰比小于0.25,含有大量的硅灰等微细组分,这有利于颗粒的最优紧密堆积。硅灰的表面化学效应以及较大的表面积使其成为UHSC中最难被分散的组分。由甲基丙烯酸、甲基丙烯酸酯及甲代... 详细信息

超高强混凝土(ultra-high strength concrete,UHSC)的水灰比小于0.25,含有大量的硅灰等微细组分,这有利于颗粒的最优紧密堆积。硅灰的表面化学效应以及较大的表面积使其成为UHSC中最难被分散的组分。由甲基丙烯酸、甲基丙烯酸酯及甲代烯丙基磺酸合成的聚羧酸系超塑化剂能使水泥颗粒被有效润湿,然而烯丙醚-马来酸酐合成的聚羧酸系超塑化剂可以很好地分散硅灰。这2种不同的聚羧酸系超塑化剂的复合可以使其拥有不同的分子结构,从而赋予超高强混凝土很好的流动性。当只加入1种聚羧酸系超塑化剂时其掺量为1%(质量分数,下同),而当加入这种复合聚羧酸系超塑化剂时掺量为0.5%就足够了。这2种类型的聚羧酸系超塑化剂的协同效应是由于它们的选择性吸附:甲基丙烯酸盐基的聚羧酸系超塑化剂主要吸附在水泥颗粒表面,而烯丙醚基聚羧酸系超塑化剂主要吸附在硅灰颗粒表面。实验表明:小分子量的有机酸阴离子(如:柠檬酸盐、葡萄糖酸盐及酒石酸盐中的阴离子)与聚羧酸系超塑化剂之间具有潜在的协同作用。只需加入0.1%的这些阴离子即可显著提高烯丙醚基聚羧酸系超塑化剂的作用效果。这些阴离子可以起到一种辅助作用,它们同时吸附在水泥颗粒表面以及硅灰颗粒表面。水泥颗粒的表面首先由这些阴离子所占据,而硅灰颗粒表面吸附了烯丙醚基聚羧酸系超塑化剂和这些阴离子。这些阴离子起到了一种很强的静电分散效应,使烯丙醚基聚羧酸系超塑化剂的空间位阻效应得到加强。虽然聚羧酸系超塑化剂阴离子具有缓凝作用,但是使用这种复合聚羧酸系仍能制备出高早强混凝土。

关键词：超高强混凝土硅灰聚羧酸系超塑化剂助剂分散机理

On the mechanistic origins of maximum strength in nanocrystalline metals

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npj Computational Materials 2020年第1期6卷 393-404页

作者： Ankit Gupta jacob gruber Satish S.Rajaram Gregory B.Thompson David L.McDowell Garritt j.Tucker Colorado School of Mines Mechanical EngineeringGoldenCO 80401USA Department of Mechanical Engineering Drexel UniversityPhiladelphiaPA 19104USA Department of Metallurgical and Materials Engineering University of AlabamaTuscaloosaAL 35487USA Department of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

The maximum strength of polycrystalline metals/alloys has been suggested to occur at nanoscale grain sizes where the governing deformation mechanism transitions from dislocation plasticity to grain boundary mediated *** tremendous progress recently uncovering links between transitions in nanoscale mechanisms and peak strength,the scientific literature is mostly devoid of any quantitative support,owing to the difficulty in measuring the resolved contribution of individual mechanisms to microstructural strain *** this study,the contribution of individual nanoscale mechanisms to the overall deformation of nanocrystalline Ni is calculated from atomistic simulations leveraging continuum-based kinematic metrics to compute mechanistic contributions to microstructural strain.

关键词： strength deformation grain

Sodium Citrate： A Universal Reducing Agent for Reduction/ Decoration of Graphene Oxide with Au Nanoparticles

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Nano Research 2011年第6期4卷 599-611页

作者： Zhe Zhang Huihui Chen Chunyan Xing Mingyi Guo Fugang Xu Xiaodan Wang Hermann j. gruber Bailin Zhang jilin Tang State Key Laboratory of Electroanaytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China Department of Chemistry Anhui University Hefei 230039 China Department of Chemistry and State Key Laboratory of Inorganic Synthesis and preparative Chemistry Jilin University Changchun 130023 China Institute of Biophysics Johannes Kepler University of Linz 4040 Linz Austria

A facile method is proposed for the synthesis of reduced graphene oxide nanosheets （RGONS） and Au nanoparticle-reduced graphene oxide nanosheet （Au-RGONS） hybrid materials, using graphene oxide （GO） as precursor and sodium citrate as reductant and stabilizer. The resulting RGONS and Au-RGONS hybrid materials were characterized by UV-vis spectroscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, atomic force microscopy, transmission electron microscopy, and X-ray diffraction. It was found that the RGONS and Au-RGONS hybrid materials formed stable colloidal dispersions through hydrogen bonds between the residual oxygen-containing functionalities on the surface of RGONS and the hydroxyl/carboxyl groups of sodium citrate. The electrochemical responses of RGONS and Au-RGONS hybrid material-modified glassy carbon electrodes （GCE） to three kinds of biomolecules were investigated, and all of them showed a remarkable increase in electrochemical performance relative to a bare GCE.

关键词： Graphene nanosheets sodium citrate Au nanoparticles hybrid materials electrocatalysis

Trans-arterial chemoperfusion for the treatment of liver metastases of breast cancer and colorectal cancer: Clinical results in palliative care patients

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World journal of Clinical Oncology 2017年第4期8卷 343-350页

作者： Tatjana gruber-Rouh Marcel Langenbach Nagy NN Naguib Nour-Eldin M Nour-Eldin Thomas j Vogl Stephan Zangos Martin Beeres Institute for Diagnostic and Interventional Radiology University Hospital Frankfurt

AIM To evaluate the clinical value and efficiency of transarterial chemoperfusion(TACp) in patients with liver metastases from breast cancer(BC) and colorectal cancer(CRC).METHODS We treated 36 patients with liver metastases of BC(n = 19, 19 females) and CRC(n = 17; 8 females, 9 males) with repeated TACp. The treatment interval was 4 wk. TACp was performed with gemcitabine(1000 mg/m2) and mitomycin(10 mg/m2), administered within 1 h after positioning the catheter tip in the hepatic artery. Before treatment, the size, location, tumour volume, vascularization and number of liver tumours were evaluated using magnetic resonance imaging(MRI). Tumour response was evaluated according to the Response Evaluation Criteria in Solid Tumors *** TACp using gemcitabine and mitomycin for metastases from CRC and BC was performed without any serious side effects. The follow-up MRI showed a therapeutic response in 84.2% of the BC patients-stable disease 47.4% and partial response 36.8%. A progression was seen in 15.8%.CRC patients showed a therapeutic response in 52.9% of cases. A progression of the disease was documented in 47.1% of the patients with CRC. These data show that TACp in patients with liver metastases of BC leads to a significantly better therapeutic response compared with CRC patients(p = 0.042). The median survival time was 13.2 mo for the BC patients, which is significantly longer than for CRC patients at 9.3 mo(p = 0.001).CONCLUSION TACp for liver metastases of BC appears to be a safe and effective palliative treatment with improved outcomes in comparison to patients with CRC.

关键词： Colorectal neoplasms Breast neoplasms Neoplasm metastasis Neoplasms Drug therapy

Magnetooptics of non-Kramers Eu^(3+) ions in garnets:analysis complemented by crystal-field splitting modeling calculations

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journal of Rare Earths 2013年第9期31卷 837-842页

作者： Uygun V.Valiev john B.gruber Anvar K.Mukhammadiev Vasiliy O.pelenovich 付德君 Gary W.Burdick Faculty of physics National University of Uzbekistan Department of physics and Astronomy The University of Texas at San Antonio School of physics and Technology Wuhan University Department of physics Andrews University

Spectra of absorption, luminescence, magnetic circular dichroism （MCD）, and magnetic circular polarization of lumines- cence （MCpL） in Gd3Ga5O12：Eu3＋ and Eu3Ga3O12 garnets were studied within the visible spectral range at 300 K. Analysis of the spectral and temperature dependences of the magnetooptical and optical spectra made it possible to identify the magneto-dipole （MD） and electro-dipole （ED） 4f→4f transitions occurring between Stark sublevels of the 7Fj （j=1, 2） and 5D0 multiplets in Eua＋-containing garnet structures. Quantum mechanical ＂mixing＂ had significant influence on quasi-degenerate states of the non-Kramers rare-earth Eu3＋ ion for Eu3GasOl2 in MCD due to forbidden MD transition 7F1→SD0 and for GdaGasOiE：EU3＋ in MCpL due to MD 4f→4f transition 5Do→7F1 and forced ED-transition 5Do→7F2. A parameterized Hamiltonian defined to operate within the entire 4f（6） ground electronic configuration of Eu3＋ ion was used to model the experimental Stark levels, including their irreducible rep- resentations and wavefunctions. The crystal-field parameters were determined through a Monte-Carlo method in which nine in- dependent crystal-field parameters, Bkq, were given random starting values and optimized using standard least-squares fitting between calculated and experimental levels. The final fitting standard deviation between 57 calculated-to-experimental levels was 0.73 meV.

关键词： : magnetic circular dichroism magnetic circular polarization luminescence adsorption garnet non-Kramers ion rare earths

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人类肿瘤疫苗的进展与展望

国外医学（肿瘤学分册） 1992年第4期19卷 224-227页

作者： Cole III jS gruber j 王雷

肿瘤是具有不同特性的一类疾病,因此开发肿瘤疫苗的可能性是复杂的。一些肿瘤与特殊病原体如病毒有关,而另外一些肿瘤的病因尚不明了。传统的疫苗研制是基于机体对某一特定疾病或肿瘤有关的特异抗原的识别能力,并激起宿主针对那些抗原... 详细信息

肿瘤是具有不同特性的一类疾病,因此开发肿瘤疫苗的可能性是复杂的。一些肿瘤与特殊病原体如病毒有关,而另外一些肿瘤的病因尚不明了。传统的疫苗研制是基于机体对某一特定疾病或肿瘤有关的特异抗原的识别能力,并激起宿主针对那些抗原的相应的保护性免疫反应。因此,传统的疫苗研制只能适用于那些主要由病毒性疾病引起的肿瘤。

关键词：肿瘤疫苗

Alanine Transaminase Individual Variation Is a Better Marker than Socio-Cultural Factors for Body Mass Increase in Healthy Males

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Food and Nutrition Sciences 2011年第10期2卷 1054-1062页

作者： Maciej Henneberg Frank j. Rühli philipp gruber Ulrich Woitek 不详

Overweight and obesity are considered a major burden on public health in developed countries. Underlying etiologies are enigmatic and metabolic causes have been suggested to various extents before. We analyze links of major blood parameters to individual body mass in a young male cohort, controlling for socio-cultural factors, in order to explore an underlying metabolic cause of obesity. Anthropometric (height, weight) physiologic (blood pressure) and metabolic data (total cholesterol, alanine transaminase, creatinine, postprandial glucose, blood cell counts, haemoglobin) of Swiss conscripts (N = 46,684;18 - 20 yrs old;2005-2007 census) were examined in the context of their socio-cultural groupings (occupation, mother tongue, religion) by ANOVA and stepwise multiple regression analysis. Swiss Armed Forces recruiting is mandatory, thus each year’s group studied reflects more than 80% of a year’s male Swiss citizen birth cohort. Individual body mass index ranged from 19 kg/m2 (5th percentile) to 29 kg/m2 (95th percentile) with a median of 22 kg/m2. BMI increases significantly, even within its normal range (18.5 - 25 kg/m2) with increases in alanine transaminase (r2 = 0.10), total cholesterol (r2 = 0.08) and erythrocyte counts (r2 = 0.02). All other parameters, including socio-cultural categories, explain individually 1% or less of total BMI variation. Glucose values do not correlate with BMI significantly, thus suggesting a specific metabolic co-etiology of individual mass increases. There may occur a biochemical anomaly in liver metabolism that underlies development of the metabolic syndrome later in life. Were it so, pharmacological intervention rather than just diet and exercise regime could be more effective treatment of obesity.

关键词： Switzerland Young Men Conscripts Obesity Language

Low-dose morphine elicits ventilatory excitant and depressant responses in conscious rats: Role of peripheral <i>µ</i>-opioid receptors

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Open journal of Molecular and Integrative physiology 2013年第3期3卷 111-124页

作者： Fraser Henderson jr. Walter j. May Ryan B. gruber Alex p. Young Lisa A. palmer Benjamin Gaston Stephen j. Lewis pediatric Respiratory Medicine University of Virginia School of Medicine Charlottesville USA Division of Biology Galleon Pharmaceuticals Horsham USA Department of pediatrics Case Western Reserve University Cleveland USA

The systemic administration of morphine affects ventilation via a mixture of central and peripheral actions. The aims of this study were to characterize the ventilatory responses elicited by a low dose of morphine in conscious rats;to determine whether tolerance develops to these responses;and to determine the potential roles of peripheral μ-opioid receptors (μ-ORs) in these responses. Ventilatory parameters were monitored via unrestrained whole-body plethysmography. Conscious male Sprague-Dawley rats received an intravenous injection of vehicle or the peripherally-restricted μ-OR antagonist, naloxone methiodide (NLXmi), and then three successive injections of morphine (1 mg/kg) given 30 min apart. The first injection of morphine in vehicle-treated rats elicited an array of ventilatory excitant (i.e., increases in frequency of breathing, minute volume, respiratory drive, peak inspiratory and expiratory flows, accompanied by decreases in inspiratory time and end inspiratory pause) and inhibitory (i.e., a decrease in tidal volume and an increase in expiratory time) responses. Subsequent injections of morphine elicited progressively and substantially smaller responses. The pattern of ventilatory responses elicited by the first injection of morphine was substantially affected by pretreatment with NLXmi whereas NLXmi minimally affected the development of tolerance to these responses. Low-dose morphine elicits an array of ventilatory excitant and depressant effects in conscious rats that are subject to the development of tolerance. Many of these initial actions of morphine appear to involve activation of peripheral μ-ORs whereas the development of tolerance to these responses does not.

关键词： Morphine Minute Ventilation Tolerance peripheral and Central Opioid Receptors Conscious Rats

Supply Mix Optimization for Decentralized Energy Systems

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Open journal of Applied Sciences 2013年第2期3卷 5-11页

作者： j. K. gruber j. L. Mínguez Fernández M. prodanovic Electrical Systems Unit IMDEA Energy Institute Móstoles (Madrid) Spain

In recent years, the energy sector has undergone an important transformation as a result of technological progress and socio-economic development. The continuous integration of renewable energy sources forces a gradual transition from the traditional business model based on a reduced number of large power plants to a more decentralized energy production. The decentralization and the increased number of energy sources lead to a series of new challenges in the energy sector. This paper presents an approach to determine the optimal energy supply mix for small and medium sized buildings or installations. The optimization algorithm considers the electricity and heat demand and determines the optimal combination of energy sources by minimizing an economic index. The optimization problem can be solved for multiple demand profiles and takes into account the possibility to integrate accumulator systems. The proposed approach provides a high degree of flexibility and can be used to study the influence of the energy prices on the optimal energy supply mix. The performance of the proposed optimization approach is illustrated by the results obtained from a simulation example.

关键词： Energy Supply Mix Optimal Configuration Decentralized Generation