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Particuology 2014年第5期12卷 116-131页

作者： alexander Krok Marin Peciar Roman Fekete Slovak University of Technology in Bratislava Faculty of Mechanical EngineeringBratislavaSlovak Republic

During the production of pharmaceutical tablets using powder compaction, certain common problems can occur, such as sticking, tearing, cutting, and lamination. In the past, the compressibility of the powder was calculated only along the axis of the device; consequently, critical areas of the material throughout the volume could not be identified. Therefore, finite element method （FEM） can be used to predict these defects in conjunction with the use of an appropriate constitutive model. This article summarizes the current research in the field of powder compaction, describes the Drucker-Prager Cap model calibration procedure and its implementation in FEM, and also examines the mechanical behavior of powder during compaction. In addition, the mechanical behavior of pharmaceutical powders in relation to changes in friction at the wall of the system is examined, and the dependence of lubrication effect on the geometry of the compaction space is also investigated. The influence of friction on the compaction process for the flat-face, fiat-face radius edge, and standard convex tablets is examined while highlighting how the effects of friction change depending on the shape of these tablets.

关键词： Powder Die compaction FEM

Implications of membrane fouling toward the removal of the pharmaceutical sulfamethoxazole by nanofiltration processes

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第8期12卷 575-582页

作者： alexander SIMON William PRICE Long Duc NGHIEM School of Civil Mining and Environmental Engineering the University of Wollongong School of Chemistry the University of Wollongong

The influence of membrane fouling on the retention of the trace organic contaminant sulfamethoxazole by a nanofiltration(NF) process was *** fouling caused a severe flux decline possibly due to pore blocking and adsorption directly after the commencement of the fouling layer *** membrane-foulant interactions were absent for colloidal fouling,which resulted in a more gradual flux *** charge played a significant role in the separation process of inorganic salts,where the retention was the highest in a caustic environment(high pH) due to more swollen membrane material caused by the higher negative charge on the *** fouling and a combination of colloidal and organic fouling led to a significant increase in the membrane negative *** influence of membrane fouling on solute retention was dependent on the fouling behaviour and the physicochemical properties of the model foulants,where the model foulants probably contributed to an increase in the retention of charged solutes due to enhanced electrostatic *** fouling caused an increase in the retention of inorganic salts and sulfamethoxazole due to pore *** contrast,colloidal fouling caused a decrease in the retention of inorganic salts due to cake-enhanced concentration ***,the presence of a colloidal fouling layer did not reduce the retention of sulfamethoxazole.A mixture of colloidal and organic matter improved the retention of inorganic salts.A similar conclusion can be inferred for sulfamethoxazole at pH 4 when the compound exists in a neutral form.

关键词： Nanofiltration(NF) Organic fouling Colloidal fouling Combined fouling Trace organics Water reuse

On random coefficient INAR(1) processes

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Science China Mathematics 2013年第1期56卷 177-200页

作者： ROITERSHTEIN alexander ZHONG Zheng Department of Mathematics Iowa State University

The random coefficient integer-valued autoregressive process was introduced by Zheng,Basawa,and Datta in *** this paper we study the asymptotic behavior of this model(in particular,weak limits of extreme values and the growth rate of partial sums) in the case where the additive term in the underlying random linear recursion belongs to the domain of attraction of a stable law.

关键词： models for count data thinning models branching processes random environment limit theorems

'Hippocampal innate inflammatory gliosis only'-the future role of surgery in a novel temporal lobe epilepsy syndrome

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Neural Regeneration Research 2023年第12期18卷 2657-2658页

作者： alexander Grote Daniel Delev Clinic for Neurosurgery University Hospital of MarburgMarburgGermany(Grote A)Clinic for NeurosurgeryUniversity Medical Center AachenAachenGermany

Epilepsy is one of the most common neurological conditions affecting more than 50 million people worldwide(https://***/news-room/fact-sheets/detail/epilepsy).Despite numerous antiseizure medications(ASM),approximately 30%of all patients will develop drug-resistant epile psy(DRE).DRE leads to devastating health and socioeconomic consequences(Luoni et al.,2011).

关键词： epilepsy al. surgery

How to select the optimal treatment for first line metastatic colorectal cancer

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World Journal of Gastroenterology 2014年第4期20卷 899-907页

作者： alexander Stein Carsten Bokemeyer Department of Oncology Haematology Stem Cell Transplantation with the Section Pneumology Hubertus Wald Tumor Centre University Cancer Centre Hamburg University Medical Centre Hamburg-Eppen-dorf 20246 Hamburg Germany

Choice of first line treatment for patients with metastatic colorectal cancer(mCRC)is based on tumour and patient related factors and molecular information for determination of individual treatment aim and thus treatment *** advances(e.g.,extended RAS testing)enable tailored patient assignment to the most beneficial treatment *** fluoropyrimidines,irinotecan and oxaliplatin,a broad variety of molecular targeting agents are currently available,e.g.,anti-angiogenic agents(bevacizumab)and epidermal growth factor receptor(EGFR)antibodies(cetuximab,panitumumab)for first line treatment of *** some combinations should be avoided(e.g.,oral or bolus fluoropyrimidines,oxaliplatin and EGFR antibodies),treatment options range from single agent to highly effective four-drug *** data comparing EGFR antibodies and bevacizumab,both with chemotherapy,seem to favour EGFR antibodies in RAS wildtype ***,choosing the most appropriate treatment approach for mCRC patients remains a complex issue,with numerous open questions.

关键词： Colorectal cancer Metastatic Induction chemotherapy Epidermal growth factor receptor

Constitutive Laws of the Underground Opening Collapse due to Dynamic Load

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Transactions of Tianjin University 2008年第B10期14卷 483-490页

作者： alexander BUDKOV Gevorg KOCHARYAN Institute for Dynamics of Geospheres Russian Academy of Sciences Moscow Russia

The constitutive laws of the collapse of underground openings in a rock massif were in-vestigated based on the results of laboratory and field experiments, and computations using ana-lytical and numerical models. It is shown that the principal mechanism of failure of underground openings over important for practice peak particle velocity amplitude range of 1 to 10 m/s is the roof and wall breakage due to the fall of key blocks. Over this load range the material crushing is of considerably less importance. The geometry of discontinuities influences mainly the stability of key blocks. Further caving depends weakly on block structure of near-tunnel zone. The mean volume of fall material is a rather stable quantity for rock massifs of different structures. Lower tunnel sta-bility in the zones of high fracturing is caused by a higher probability of the presence of the unsta-ble key blocks and the decrease of strength characteristics of fractured bounding blocks. The de-crease of average block size is a less important accompanying factor.

关键词： explosion underground opening rock discontinuity key block dynamic load

MtDNA mutations and aging--not a closed case after all?

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Signal Transduction and Targeted Therapy 2021年第3期6卷 555-556页

作者： alexander M.Wolf Laboratory for Morphological and Biomolecular Imaging Faculty of MedicineNippon Medical SchoolTokyoJapan

In a recent paper in Nature Cancer,Smith et *** that mitochondrial DNA(mtDNA)mutations can confer a growth advantage to intestinal tumors by remodeling cell metabolism,particularly toward elevated de novo serine synthesis.1 For the reasons outlined below,in the past decade,the field of mtDNA biology has experienced a relative loss of *** findings of Smith et *** welcome new life into the complex field of mtDNA contributions to aging and cancer.

关键词： al. metabolism elevated

Evolutionary status of T Tauri stars

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Research in Astronomy and Astrophysics 2018年第8期18卷 103-110页

作者： Olga Eretnova alexander Dudorov Physics Department Chelyabinsk State University

The problem of determining the masses and ages of T Tauri star （TTS） using their evolu- tionary status is discussed. We test four pre-main sequence evolutionary models using well determined observational parameters of 12 binary TTSs and two binary red dwarfs. It is shown that the masses derived using the tracks of all models are in good agreement with flhe masses obtained from the obser- vations of TTSs with masses M 〉 0.7 Me （mean error ε,- 10%）. Low-mass stars with M ≤ 0.7 M⊙ have significantly greater mean error; e - 50% for the tracks of Bressan et al. and Chen et al., and e - 30% for the other tracks. The isochrones of all tested evolutionary models diverge for stars with masses M ≤ 0.7 M⊙. The difference increases with the mass decrease and can reach 10% of Kelvin- Helmholtz time for stars with mass M = 0.2 Me. The ages of most of the considered TTSs are smaller than the Kelvin-Helmholtz time. This confirms their evolutionary status of being pre-main sequence stars.

关键词： stars pre-main sequence stars - stars binaries - Hertzsprung-Russell diagram

Schreier rewriting beyond the classical setting Dedicated to our teacher Alfred Lvovich Shmelkin on his 70th birthday

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Science China Mathematics 2009年第2期52卷 231-243页

作者： BAHTURIN Yuri OLSHANSKII alexander Department of Mathematics and Statistics Memorial University of Newfoundland St. John'sNL A1C 5S7Canada Department of Algebra Faculty of Mathematics and Mechanics119899 Moscow Russia Department of Mathematics 1326 Stevenson Center Vanderbilt UniversityNashvilleTN 37240 USA

Using actions of free monoids and free associative algebras, we establish some Schreier-type formulas involving ranks of actions and ranks of subactions in free actions or Grassmann-type relations for the ranks of intersections of subactions of free actions. The coset action of the free group is used to establish a generalization of the Schreier formula in the case of subgroups of infinite index. We also study and apply large modules over free associative and free group algebras.

关键词： free algebra group monoid act G-set module

Carbon and Oxygen Isotopic Composition of Surface-Sediment Carbonate in Bosten Lake (Xinjiang,China) and its Controlling Factors

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Acta Geologica Sinica(English Edition) 2009年第2期83卷 386-395页

作者： Steffen MISCHKE alexander PROKOPENKO Freie University Berlin BerlinGermany Department of Geological Sciences University of South CarolinaColumbiaSouth CarolinaUSA

Bosten Lake is a mid-latitude lake with water mainly supplied by melting ice and snow in the Tianshan Mountains. The depositional environment of the lake is spatially not uniform due to the proximity of the major inlet and the single outlet in the western part of the lake. The analytical results show that the carbon and oxygen isotopic composition of recent lake sediments is related to this specific lacustrine depositional environment and to the resulting carbonate mineralogy. In the southwestern lake region between the Kaidu River inlet and the Kongqi River outlet, carbon isotope composition （δ^13C） values of the carbonate sediment （-1‰ to -2‰） have no relation to the oxygen isotope composition of the carbonate （δ^18O） values （-7‰ to -8‰）, with both isotopes showing a low variability. The carbonate content is low （〈20%）. Carbonate minerals analyzed by X-ray diffraction are mainly composed of calcite, while aragonite was not recorded. The salinity of the lake water is low in the estuary region as a result of the Kaidu River inflow. In comparison, the carbon and oxygen isotope values are higher in the middle and eastern parts of the lake, with δ^13C values between approximately ＋0.5‰ and ＋3‰, and δ^18O values between -1‰ and -5‰. There is a moderate correlation between the stable oxygen and carbon isotopes, with a coefficient of correlation r of approximately 0.63. This implies that the lake water has a relatively short residence time. Carbonate minerals constitute calcite and aragonite in the middle and eastern region of the lake. Aragonite and Mg-calcite are formed at higher lake water salinity and temperatures, and larger evaporation effects. More saline lake water in the middle and eastern region of the lake and the enhanced isotopic equilibrium between water and atmospheric CO2 cause the correlating carbon and oxygen isotope values determined for aragonite and Mg-calcite. Evaporation and biological processes are the main reasons for the salinity and carbonate mi

关键词： carbonate aragonite calcite stable carbon and oxygen isotope composition Bosten Lake