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Chinese Chemical Letters 2011年第10期22卷 1179-1182页

作者： Barahman Movassagh amir Rakhshani Department of Chemistry K.N.Toosi University of TechnologyP.O.Box 16315-1618TehranIran

Potassium tert-butoxide has been found to be a highly efficient catalyst for one-pot,three-component reaction of aryl aldehydes, acetophenones,and thiols via Claisen-schmidt/Michael addition reactions for the synthesis of thia-Michael adducts in high yields. The reactions are best carried out in tert-butyl alcohol at room temperature.

关键词： Potassium tert-butoxide Thia-Michael adduct Three-component reaction C-s bond formation Thiols

Biological treatment of chicken feather waste for improved biogas production

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Journal of Environmental sciences 2011年第10期23卷 1747-1753页

作者： Gergely Forgcs saeid Alinezhad amir Mirabdollah Elisabeth Feuk-Lagerstedt Ilona srvri Horvth school of Engineering University of Bors501 90 BorsSweden Department of Chemical and Biological Engineering Chalmers University of Technology412 96 GteborgSweden school of Engineering University of Boras501 90 BorsSweden

A two-stage system was developed which combines the biological degradation of keratin-rich waste with the production of biogas. Chicken feather waste was treated biologically with a recombinant Bacillus megaterium strain showing keratinase activity prior to biogas production. Chopped, autoclaved chicken feathers （4%, W/V） were completely degraded, resulting in a yellowish fermentation broth with a level of 0.51 mg/mL soluble proteins after 8 days of cultivation of the recombinant strain. During the subsequent anaerobic batch digestion experiments, methane production of 0.35 Nm3/kg dry feathers （i.e., 0.4 Nm3/kg volatile solids of feathers）, corresponding to 80% of the theoretical value on proteins, was achieved from the feather hydrolyzates, independently of the pre- hydrolysis time period of 1, 2 or 8 days. Cultivation with a native keratinase producing strain, Bacillus licheniformis resulted in only 0.25 mg/mL soluble proteins in the feather hydrolyzate, which then was digested achieving a maximum accumulated methane production of 0.31 Nm3/kg dry feathers. Feather hydrolyzates treated with the wild type B. megaterium produced 0.21 Nm3 CH4/kg dry feathers as maximum yield.

关键词： anaerobic digestion feather waste keratinase, Bacillus licheniformis Bacillus megaterium gene expression

On Non-standard Hilbert Functions

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Algebra Colloquium 2018年第1期25卷 71-80页

作者： amir Bagheri Rahim Rahmati-Asghar Marand Technical Coflege University of Tabriz Tabriz Iran School of Mathematics Institute for Research in Fundamental Sciences (IPM) Department of Mathematics Faculty of Basic Sciences University of Maragheh

. Let s = k[x1,..., xn] be a non-standard polynomial ring over a field k and let M be a finitely generated graded s-module. In this paper, we investigate the behaviour of Hilbert function of M and its relations with lattice point counting. More precisely, by using combinatorial tools, we prove that there exists a polytope such that the image of Hilbert function in some degree is equal to the number of lattice points of this polytope.

关键词： polynomial ring non-standard Hilbert function Hermite normal form

Early versus delayed necrosectomy in pancreatic necrosis:A population-based cohort study on readmission,healthcare utilization,and in-hospital mortality

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World Journal of Methodology 2024年第3期14卷 55-67页

作者： Hassam Ali Faisal Inayat Vinay Jahagirdar Fouad Jaber Arslan Afzal Pratik Patel Hamza Tahir Muhammad sajeel Anwar Attiq Ur Rehman Muhammad sarfraz Ahtshamullah Chaudhry Gul Nawaz Dushyant singh Dahiya amir H sohail Muhammad Aziz Division of Gastroenterology and Hepatology East Carolina University Brody School of MedicineGreenvilleNC 27834United States Department of Internal Medicine Allama Iqbal Medical CollegeLahorePunjab 54550Pakistan Department of Internal Medicine University of Missouri-Kansas CityKansas CityMO 64108United States Division of Gastroenterology Mather Hospital and Zucker School of Medicine at Hofstra UniversityPort JeffersonNY 11777United States Department of Internal Medicine Jefferson Einstein HospitalPhiladelphiaPA 19141United States Department of Internal Medicine UHS Wilson Medical CenterJohnson CityNY 13790United States Division of Gastroenterology and Hepatology Geisinger Wyoming Valley Medical CenterWilkes-BarrePA 18711United States Department of Internal Medicine St.Dominic's HospitalJacksonMS 39216United States Division of Gastroenterology Hepatologyand MotilityThe University of Kansas School of MedicineKansas CityKS 66160United States Department of surgery University of New Mexico School of MedicineAlbuquerqueNM 87106United States Division of Gastroenterology and Hepatology The University of ToledoToledoOH 43606United States

BACKGROUND Acute necrotizing pancreatitis is a severe and life-threatening *** poses a considerable challenge for clinicians due to its complex nature and the high risk of *** minimally invasive and open necrosectomy procedures have been *** advancements in treatment modalities,the optimal timing to perform necrosectomy lacks *** To evaluate the impact of necrosectomy timing on patients with pancreatic necrosis in the United *** A national retrospective cohort study was conducted using the 2016-2019 Nationwide Readmissions *** with non-elective admissions for pancreatic necrosis were *** participants were divided into two groups based on the necrosectomy timing:The early group received intervention within 48 hours,whereas the delayed group underwent the procedure after 48 *** various intervention techniques included endoscopic,percutaneous,or surgical *** major outcomes of interest were 30-day readmission rates,healthcare utilization,and inpatient *** A total of 1309 patients with pancreatic necrosis were *** propensity score matching,349 cases treated with early necrosectomy were matched to 375 controls who received delayed *** early cohort had a 30-day readmission rate of 8.6% compared to 4.8%in the delayed cohort(P=0.040).Early necrosectomy had lower rates of mechanical ventilation(2.9%vs 10.9%,Pseptic shock(8%vs 19.5%,Pspital mortality(1.1%vs 4.3%,P=0.01).Patients in the early intervention group incurred lower healthcare costs,with median total charges of $52202 compared to$147418 in the delayed *** in the early cohort also had a relatively shorter median length of stay(6 vs 16 days,Psectomy did not significantly influence the risk of 30-day readmission,with a hazard ratio of 0.56(95%confidence interval:0.31-1.02,P=0.06).CONCLUsION Our findings show that

关键词： Acute necrotizing pancreatitis Pancreatic necrosis Early necrosectomy Delayed necrosectomy Readmission,Healthcare costs Mortality

TransPolymer: a Transformer-based language model for polymer property predictions

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npj Computational Materials 2023年第1期9卷 1703-1716页

作者： Changwen Xu Yuyang Wang amir Barati Farimani Department of Materials science and Engineering Carnegie Mellon University5000 Forbes AvePittsburgh 15213 PAUSA Department of Mechanical Engineering Carnegie Mellon University5000 Forbes AvePittsburgh 15213 PAUSA Machine Learning Department Carnegie Mellon University5000 Forbes AvePittsburgh 15213 PAUSA Department of Chemical Engineering Carnegie Mellon University5000 Forbes AvePittsburgh 15213 PAUSA

Accurate and efficient prediction of polymer properties is of great significance in polymer ***,expensive and time-consuming experiments or simulations are required to evaluate polymer ***,Transformer models,equipped with self-attention mechanisms,have exhibited superior performance in natural language ***,such methods have not been investigated in polymer ***,we report TransPolymer,a Transformer-based language model for polymer property *** proposed polymer tokenizer with chemical awareness enables learning representations from polymer *** experiments on ten polymer property prediction benchmarks demonstrate the superior performance of ***,we show that TransPolymer benefits from pretraining on large unlabeled dataset via Masked Language *** results further manifest the important role of self-attention in modeling polymer *** highlight this model as a promising computational tool for promoting rational polymer design and understanding structure-property relationships from a data science view.

关键词： property polymer rational

A review on the cracking,baking and leaching processes of rare earth element concentrates

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Journal of Rare Earths 2017年第8期35卷 739-752页

作者： Farzaneh sadri amir Mohammad Nazari Ahmad Ghahreman Department of Mining Engineering Queen's University 25 Union Street Kingston Ontario K7L 3N6 Canada

Rare earth elements（REE） are a set of seventeen chemical elements in the periodic table, which have been found in a variety classes of minerals in the world. The global demand for REE and their compounds has increased in high-tech applications over the past decades due to their chemical, catalytic, electrical, magnetic, and optical properties. After mining, comminution and ore beneficiation, hydrometallurgical and pyrometallurgical processes are carried out to recover REE compounds. The concentrate cracking is a process wherein the structure of a REE mineral is modified in order to dissolve REE in a weak acid solution. This would be accomplished through various techniques such as alkaline cracking and acid baking. The cracked concentrate is then leached to dissolve REE in a solution and subsequently recover those via neutralization, precipitation or solvent extraction methods. This paper reviewed the cracking and leaching methods applied to REE concentrates to produce an intermediate product for further REE separation.

关键词： rare earth elements alkaline cracking acid baking leaching separation

statistical design and kinetic and thermodynamic studies of Ni(Ⅱ) adsorption on bentonite

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Journal of Central south University 2017年第7期24卷 1529-1536页

作者： Bahareh sadeghalvad amir Reza Azadmehr Hassan Motevalian Department of Mining&Metallurgical Engineering Amirkabir University of TechnologyTehranIran

The adsorption of the bentonite toward Ni(II) from aqueous solution was studied to obtain optimum conditions,equilibrium model,thermodynamic and kinetic *** method was used to evaluate maximum amount of adsorbed Ni(II).In this work,p H of solution during stirring,contact time,initial Ni(II) concentration,particle size of bentonite and amount of bentonite were considered as effective parameters which should be *** increase of temperature has negative effect on the Ni(II) *** equilibrium data were correlated well with Freundlich and Dubinin–Radushkevich isotherm models the correlation coefficients of which are(R^2) 0.994 and 0.971,*** model indicates heterogeneous and chemical absorption or ion exchange *** values of thermodynamic parameters such as ΔH°,Δs° and ΔG° of nickel adsorption reveal that it is a spontaneous,exothermic and associative *** experimental data fit the pseudo-second-order kinetic very well with correlation coefficient(R^2) more than 0.995.

关键词： bentonite adsorption experimental design optimum condition equilibrium

Experimental determination of gas holdup and volumetric mass transfer coefficient in a jet bubbling reactor

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Chinese Journal of Chemical Engineering 2021年第6期34卷 61-67页

作者： Mostafa Abbasian-arani Mohammad sadegh Hatamipour amir Rahimi Chemical Engineering Department University of IsfahanIsfahanIran

The hydrodynamics and mass transfer characteristics of a lab-scale jet bubbling reactor(JBR)including the gas holdup,volumetric mass transfer coefficient and specific interfacial area were assessed experimentally investigating the influence of temperature,pH and superficial gas *** reactor diameter and height were 11 and 30 cm,*** was equipped with a single sparger,operating at atmospheric pressure,20 and 40℃,and two pH values of 3 and *** height of the liquid was 23 cm,while the superficial gas velocity changed within 0.010-0.040 m·s^(-1)*** were conducted with pure oxygen as the gas phase and saturated lime solution as the liquid *** liquid-side volumetric mass transfer coefficient was determined under unsteady-state oxygen absorption in a saturated lime *** gas holdup was calculated based on the liquid height change,while the specific interfacial area was obtained by a physical method based on the bubble size distribution(BsD)in different superficial gas *** results indicated that at the same temperature but different pH,the gas holdup variation was negligible,while the liquid-side volumetric mass transfer coefficient at the pH value of 6 was higher than that at the pH=*** a constant pH but different temperatures,the gas holdup and the liquid-side volumetric mass transfer coefficients at 40℃were higher than that of the same at 20℃.A reasonable and appropriate estimation of the liquid-side volumetric mass transfer coefficient(kla)in a pilot-scale JBR was provided which can be applied to the design and scale-up of JBRs.

关键词： Jet bubbling reactor Liquid-side volumetric mass transfer coefficient Gas holdup specific interfacial area Experimental analysis

Triple non-invasive diagnostic test for exclusion of common bile ducts stones before laparoscopic cholecystectomy

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World Journal of Gastroenterology 2007年第43期13卷 5745-5749页

作者： Bahram Pourseidi amir Khorram-Manesh Department of surgery Kerman University of Medical Science Kerman Iran Department of surgery Kung?lv and sahlgrenska University Hospitals Gteborg Sweden

AIM: To evaluate the impact of a preoperative "triple non-invasive diagnostic test" for diagnosis and/or exclusion of common bile duct stones. METHODs: All patients with symptomatic gallstone disease, operated on by laparoscopic cholecystectomy from March 2004 to March 2006 were studied retrospectively. Two hundred patients were included and reviewed by using a triple diagnostic test including: patient's medical history, routine liver function tests and routine ultrasonography. All patients were followed up 2-24 mo after surgery to evaluate the impact of triple diagnostic test. REsULTs: Twenty-five patients were identified to have common bile duct stones. Lack of history of stones, negative laboratory tests and normal ultrasonography alone was proven to exclude common bile duct stones in some patients. However, a combination of these three components (triple diagnostic), was proven to be the most statistically significant test to exclude common bile duct stones in patients with gallstone disease. CONCLUsION: Using a combination of routinely used diagnostic components as triple diagnostic modality would increase the diagnostic accuracy of common bile duct stones preoperatively. This triple non-invasive test is recommended for excluding common bile duct stones and to identify patients in need for other investigations.

关键词： Common bile duct stones Laparoscopic cholecystectomy Triple non-invasive diagnostic test

Evaluating the efficiency of the Dong model in determining fire vulnerability in Iran’s Zagros forests

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Journal of Forestry Research 2019年第4期30卷 1447-1458页

作者： sabri Baqer Rasooli amir Eslam Bonyad Department of Geography College of EducationUniversity of GarmianKalarKurdistan RegionIraq Department of Forestry Faculty of Natural ResourcesUniversity of GuilanSowmeh SaraIran

Recent fires in Iran’s Zagros forests have inflicted heavy,extensive losses to the environment,forests,villages,and forest inhabitants,resulting in a huge financial loss to the *** the increasing risk of fire and the resulting losses,it has become ever more necessary to design and develop efficient fire control and prediction *** present study utilizes the Dong model to develop a map of areas vulnerable to fire in the Zarivar lake forests as a representative sample of Zagros *** model uses as its inputs some of the most significant factors(such as vegetation,physiographic features,and the human component)that affect the fire occurrence and *** assigned weights to each factor based on the model,all maps were overlapped in the ArcMap and then the region was divided into five *** results showed that 74%of the region was located in three classes:highly vulnerable,vulnerable,and medially *** validate the proposed zoning map it was compared with a map based on real data obtained from previous *** results showed that 81%of fire incidents were located in highly vulnerable,vulnerable and medially vulnerable ***,the findings indicated a medium to a high degree of fire vulnerability in Zarivar Lake forests.

关键词： Dong model Fire incidents Zarivar lake Zoning