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Use of breakthrough experiment to evaluate the performance of hydrogen isotope separation for metal-organic frameworks m-mOF-74(m=Co, Ni, mg, Zn)

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Science China Chemistry 2020年第7期63卷 881-889页

作者： Yanan Si Wenjing Wang el-Sayed m.el-Sayed Daqiang Yuan State Key Laboratoty of Structural Chemistry Fujian Institute o f Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of the Chinese Academy of Sciences Beijing 100049China Chemical Refining Laboratory Refining DepartmentEgyptian Petroleum Research InstituteNasr CityCairoEgypt

The unique adsorption performance of metal-organic frameworks(mOFs) indicates a new direction for gas separation and purification. The low-temperature distillation, as a traditional technique for hydrogen isotope separation, is limited as it is a high energy-and cost-intensive process. Instead of utilizing such a conventional separation route, we use ordered microporous frameworks based on a physical adsorption mechanism to solve the challenge of hydrogen isotope separation. Herein we analyze m-mOF-74(m=Co, Ni, mg, Zn), featuring a hexagonal channel about 11 ? and high density of open metal sites, for their ability to separate and purify deuterium from the hydrogen isotope mixture by dynamic column breakthrough experiments. Our results show that the combination of the strength of binding sites, density of coordinatively unsaturated metal sites and hydrogen isotope adsorption capacity of materials renders Co-mOF-74 as an optimal adsorbent for the capture of deuterium from hydrogen isotope mixtures in a simulated industrial process.

关键词： hydrogen isotope separation breakthrough experiment mOF-74

Use of thiopurines in inflammatory bowel disease: Safety issues

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World Journal of Gastrointestinal Pharmacology and Therapeutics 2014年第2期5卷 63-76页

作者： Anastasia Konidari wael el matary Department of Paediatric Gastroenterology Alder Hey Children’s NHS Foundation TrustLiverpool L12 2APUnited Kingdom Section of Paediatric Gastroenterology Department of Paediatrics Faculty of MedicineUniversity of Mani-tobaManitoba R3A 1S1Canada

Thiopurines are widely used for maintenance treatment of inflammatory bowel disease. Interindividual variability in clinical response to thiopurines may be attributed to several factors including genetic polymorphisms, severity and chronicity of disease, comorbidities, duration of administration, compliance issues and use of concomitant medication, environmental factors and clinician and patient preferences. The purpose of this review is to summarise the current evidence on thiopurine safety and toxicity, to describe adverse drug events and emphasise the significance of drug interactions, and to discuss the relative safety of thiopurine use in adults, elderly patients, children and pregnant women. Thiopurines are safe to use and well tolerated, however dose adjustment or discontinuation of treatment must be considered in cases of non-response, poor compliance or toxicity. Drug safety, clinical response to treatment and short to long term risks and benefits must be balanced throughout treatment duration for different categories of patients. Treatment should be individualised and stratified according to patient requirements. Enzymatic testing prior to treatment commencement is advised. Surveillance with regular clinic follow-up and monitoring of laboratory markers is important. Data on long term efficacy, safety of thiopurine use and interaction with other disease modifying drugs are lacking, especially in paediatric inflammatory bowel disease. High quality, collaborative clinical research is required so as to inform clinical practice in the future.

关键词： Thiopurines Azathioprine mercaptopurine Inflammatory bowel disease Adult Children Therapeutic drug monitoring

沉积成因Sr/Ba指示的福建潮控海湾全新世沉积环境及海平面意义

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海洋地质与第四纪地质 2024年第5期44卷 95-106页

作者：陈能邱彬焕张杰余欢刘演 el Said Shetaia 孙千里于俊杰陈静华东师范大学河口海岸学国家重点实验室上海200241 华东师范大学地理科学学院上海200241 中国地质调查局南京地质调查中心南京210016

福建沿海多发育潮控型海湾,潮滩平坦宽广,海湾水深较浅,有孔虫等微体生物较为匮乏,且其化石在地层中保存相对较差,致使沉积微相辨识存在一定难度,从而限制了深入理解该区全新世海平面变化过程及沉积环境响应。本研究拟利用不受保存环境... 详细信息

福建沿海多发育潮控型海湾,潮滩平坦宽广,海湾水深较浅,有孔虫等微体生物较为匮乏,且其化石在地层中保存相对较差,致使沉积微相辨识存在一定难度,从而限制了深入理解该区全新世海平面变化过程及沉积环境响应。本研究拟利用不受保存环境限制的沉积成因Sr/Ba指标,探索其在福建宁德三沙湾地区沉积微相的辨识潜力,并结合AmS 14C年龄,探讨该区全新世以来的沉积环境演化及区域海平面变化。结果表明:①沉积成因Sr/Ba在三沙湾潮滩和海湾表层沉积物中平均值分别为9.06和20.43,具有显著差异。潮滩沉积物中的Sr/Ba明显高于长江等大河口地区(1~3),这是该区淡水输入量较少、潮滩盐度较高所致,这说明该指标辨识海陆过渡沉积相时需要考虑区域水文特点。②晚第四纪NDGK2钻孔沉积物Sr/Ba自下而上可分为3层(Ⅰ—Ⅲ):层Ⅰ为杂色硬黏土,Sr/Ba比值全孔最低(均值5.29),但也高于淡水环境,推测为前期海相沉积物的暴露改造;层Ⅱ—Ⅲ均为深灰色黏土,其中层Ⅱ均值为10.77,接近潮滩相;层Ⅲ均值为全孔最高(13.44),接近海湾相。结合AmS 14C年龄可知,NDGK2钻孔的河漫滩-潮滩-海湾沉积相演化受控于全新世海平面上升过程,潮滩相形成于约8.9 ***,当时该区海平面大约在−21.0±2.5 m,最大海泛面出现于约8.2 ***,之后出现了长达6 ka的低沉积速率时期,直至约2.2 ***海湾内加速沉积。③该区15个钻孔全新统底部Sr/Ba均显现出明显的潮滩相特征,这为重建区域全新世相对海平面提供了可行性。

关键词：潮控海湾沉积成因Sr/Ba 潮滩相沉积环境海平面变化全新世

Evaluating pediatric ureteropelvic junction obstruction:Dynamic magnetic resonance urography vs renal scintigraphy 99mtechnetium mercaptoacetyltriglycine

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World Journal of Radiology 2024年第3期16卷 49-57页

作者： Yousuf Al-Shaqsi matthieu Peycelon Annabel Paye-Jaouen elisabeth Carricaburu Anca Tanase Christine Grapin-Dagorno Alaa el-Ghoneimi Department of Pediatric Surgery Sultan Qaboos University HospitalMuscat 123Oman Service de Chirurgie Viscérale et Urologie Pédiatrique Hôpital Universitaire Robert-DebréAssistance-Publique Hôpitaux de ParisParis 75019France Centre de Références maladies Rares Malformations Rares des Voies Urinaires(MARVU)Paris 97019France Facultéde médecine Universitéde ParisParis 75006France Service d’Imagerie Pédiatrique Hôpital Universitaire Robert-DebréAssistance-Publique Hôpitaux de ParisParis 75019France UniversitéParis 13 Sorbonne Paris CitéParis 75013France

BACKGROUND Ureteropelvic junction obstruction(UPJO)is a common congenital urinary tract disorder in *** can be diagnosed as early as in utero due to the presence of hydronephrosis or later in life due to symptomatic *** To evaluate the discrepancy between dynamic contrast-enhanced magnetic resonance urography(dmRU)and scintigraphy 99m-technetium mercaptoacetyltriglycine(mAG-3)for the functional evaluation of *** Between 2016 and 2020,126 patients with UPJO underwent surgery at Robert Debré*** these,83 received a prenatal diagnosis,and 43 were diagnosed during *** of the 126 patients underwent surgery based on the clinical situation and postnatal ultrasound findings without undergoing functional imaging *** renal function was evaluated preoperatively using scintigraphy mAG-3(n=28),dmRU(n=53),or both(n=40).In this study,we included patients who underwent surgery for UPJO and scintigraphy mAG-3+dmRU but excluded those who underwent only scintigraphy mAG-3 or *** patients were divided into groups A(10%discrepancy).We examined the discrepancy in split renal function between the two modalities and investigated the possible risk *** The split renal function between the two kidneys was compared in 40 patients(28 boys and 12 girls)using scintigraphy mAG-3 and *** renal function,as determined using both modalities,showed a difference of10%in 9 *** of the relative renal function using dmRU revealed an excellent correlation coefficient with renal scintigraphy mAG-3 for both *** Our findings demonstrated that dmRU is equivalent to scintigraphy mAG-3 for evaluating split renal function in patients with UPJO.

关键词： Uteropelvic junction obstruction Scintigraphy 99m-technetium mercaptoacetyltriglycine magnetic resonance imaging Dynamic contrast-enhanced magnetic resonance urography

Nuclear radiation shielding effectiveness and corrosion behavior of some steel alloys for nuclear reactor systems

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Defence Technology（防务技术） 2019年第4期15卷 621-628页

作者： m.m. Sadawy R.m. el Shazly mining and Petroleum Engineering Department Al-Azhar University Nasr City Cairo 11371 Egypt Physics Department Faculty of Science Al-Azhar University Nasr City Cairo 11884 Egypt

Different types of nuclear parameters and corrosion behavior were deduced for carbon steel(AISI 1018),austenitic(304 SS),and duplex(2507 SS)stainless steel *** types of neutron energies as well as nine gamma ray energy lines(121.78-1407.92 keV)were used to evaluate the macroscopic neutron cross-sections(∑,cm^-1)and mass attenuation coefficients[σ,cm^2·g^-1)of gamma ray *** corrosion behavior was investigated using different electrochemical *** results showed that the stainless-steel alloys had a good attitude than that of carbon steel alloy for neutron and gamma ray parameters,especially the duplex stainless *** calculated values of mass attenuation coefficient using WinXcom computer program(Version 3.1),exhibited a very good agreement with the experimental values of that ***,the results indicated that duplex stainless-steel exhibited corrosion resistance higher than 304 SS and AISI 1018 steel alloys.

关键词： Steel alloys macroscopic cross-section mass attenuation coefficient Passive film Pitting

First-principles prediction of the magnetism of 4f rare-earth-metal-doped wurtzite zinc oxide

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Journal of Rare Earths 2014年第8期32卷 715-721页

作者： A.G.el Hachimi H.Zaari A.Benyoussef m.el Yadari A.el Kenz Laboratoire de magnétisme et Physique des Hautes Energies LMPHE (URAC 12) Département de Physique B.P.1014 Faculté des SciencesUniversité Mohammed V-Agdal Institut of Nanomaterials and Nanotechnology Hassan II Academy of Science and Technology Department of Science Moulay Ismail University Faculté Polydisciplinaire

electronic structure and magnetic properties of wurtzite ZnO semiconductor doped with rare earth （RE=La, Ce, Pr, Pm, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb） atoms were studied using spin-polarized density functional theory based on the full-potential linear augmented plane wave （FP-LAPW） method as implemented in the Wien2k code. In this approach the generalized gradient approximation （GGA） was used for the exchange-correlation （XC） potential. Our results showed that the substitution of RE ions in ZnO induced spins polarized localized states in the band gap. moreover, the studied DmSs compounds retained half metallicity at dopant concentration x=0.625%for most of the studied elements, with 100%spin polarization at the Fermi level （EF）. The total magnetic moments of these compounds existed due to RE 4f states present at EF, while small induced magnetic moments existed on other non-magnetic atoms as well. Finally, the energy difference between far and near configurations was investigated. It was found that the room temperature ferromagnetism was possible for RE-doped ZnO at near configuration. Since the RE-RE separation was long enough （far configuration） for magnetic coupling, the system became paramagnetic or antiferromagnetic ground state.

关键词： ZnO rare earths ferromagnetism DmS electronic structure magnetic properties half-metallic RE-doped ZnO FP-LAPW method density functional theory

Radionuclides measurements and mineralogical studies on beach sands, East Rosetta Estuary, Egypt

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Chinese Journal Of Geochemistry 2013年第2期32卷 146-156页

作者： Abd el Wahab m. el Nahas H.A. Physics Department Faculty of Women for Arts Science and Education Ain Shams University Cairo P.O 11757 Egypt Nuclear materials Authority Cairo P.O. Box 530 Egypt

Radiometric measurements were carried out for the beach sands from East Rosetta estuary to determine the activity concentrations of 238 U, 226 Ra, 232 Th, and 40 K, using a Hyper Pure Germanium spectrometer, to estimate the dose rates and radiation hazard indices. The average specific activities are 778.20 Bq/kg for 238 U; 646.89 Bq/kg for 226 Ra; 621.92 and 627.85 Bq/kg for the 222 Rn daughters 214 Pb and 214 Bi respectively. The average specific activity of 232 Th is 1510.25 Bq/kg, while the calculated specific activity for 40 K has an average of 8.41 Bq/kg. The average specific activity of 235 U is 38.61 Bq/kg. The average absorbed dose rate is 1211.36 nGy/h, 20 times higher than the estimated average global primordial radiation of 60 nGy/h and 6 times higher than that of the world range (10-200 nGy/h). The radium equivalent (Ra eq ) values are from 6 to 9 times the recommended value. The internal and external hazard indices (H int , H ex ) indicate that their values are from 6 to 11 times the permissible values of these indices. These higher values may be due to the presence of economic heavy minerals containing radionuclides as zircon and monazite as well as some trace minerals, thorite and uranothorite. The mineralogical study indicates the beach sands contain heavy minerals, zircon, monazite, rutile, ilmenite, leucoxene, magnetite and garnet. The average abundance of zircon is 0.175 wt% ranging from 0.125 wt% to 0.239 wt%, while it is 0.004wt% ranging from 0.001 wt% to 0.007 wt% for monazite. The average abundance is 0.087 wt% for rutile; 2.029 wt% for ilmenite; 1.084 wt% for magnetite; 0.384 wt% for leucoxene and 0.295 wt% for garnet.

关键词：放射性核素海滩砂矿物学核素测量河口平均丰度埃及辐射测量

Petrological and mineralogical characteristics of younger granites and pegmatites in the Wadi Haleifiya area, southeastern Sinai, Egypt

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Chinese Journal Of Geochemistry 2011年第3期30卷 304-316页

作者： el Gharbawy R.I. el Feky m.G. el Galy m.m. el maadawy W.m. Faculty of Science Ain Shams Univeristy Cairo Egypt Nuclear materials Authority P.O. Box 030 Maadi Egypt

This study is concerned with the radioactivity and mineralogy of the younger granites and pegmatites in the Wadi Haleifiya area, southeastern Sinai Peninsula, Egypt. The area is occupied by metasediments, migmatites, older and younger granites. most of these rocks, especially granites, are dissected by mafic and felsic dykes as well as pegmatites. The younger granites are represented by three main varieties: monzogranites, syenogranites and alkali feldspar granites. The monzogranite consists essentially of quartz, plagioclase, potash feldspar and biotite with minor musco-vite. Iron oxide, titanite, zircon and allanite are the main accessory minerals. Syenogranite is massive, medium- to coarse-grained and commonly exhibits equigranular and hypidiomorphic textures. It is made up essentially of potash feldspar, quartz, plagioclase and biotite. Iron oxides, allanite, epidote, titanite, and zircon are accessory minerals. The alkali feldspar granite consists mainly of perthite, quartz, alkali amphibole (arfvedsonite and riebekite), biotite, sub-ordinate plagioclase and aegirine. Iron oxide, zircon and apatite are accessory minerals, whereas chlorite and sas-surite are secondary minerals. The altered monzogranite and pegmatite recorded high radioelement contents. The eU reaches up to 120 (av.=82×10-6) in the altered monzogranite and up to 55 (av.=27×10-6) in the pegmatites. The high radioactivity in the altered monzogranite is due to the presence of thorite, uranothorite and metamict zircon. In the pegmatites, it is re-lated to the presence of uranophane, uranothorite, thorite, zircon, samarskite, monazite, xenotime, magnetite, ilmen-ite, hematite and rutile.

关键词：二长花岗岩矿物学特征西奈半岛伟晶岩东南部岩石学埃及碱长花岗岩

Design, Sonosynthesis, Quantum-Chemical Calculations, and Evaluation of New mono-and Bis-pyridine Dicarbonitriles as Antiproliferative Agents

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Chinese Journal of Chemistry 2020年第5期38卷 501-508页

作者： wael Abdelgayd Ahmed Arafa modather F.Hussein Chemistry Department College of ScienceJouf UniversityP.O.Box 2014SakakaAljoufKingdom of Saudi Arabia Chemistry Department Faculty of ScienceFayoum UniversityP.O.Box 63514Fayoum CityEgypt Chemistry Department Faculty of ScienceAl-Azhar UniversityAsyut branchEgypt

A highly efficient,simple,and clean single-step sonosynthetic procedure has been sophisticated for assembling new series of mono-and bis-pyridine dicarbonitriles from ketones,HCl,and *** presented protocol is applicable for the preparation of a broad range of uniquely substituted pyridine dicarbonitriles and seems to be superior in comparison with other previously reported *** antiproliferative impact of the newly synthesized derivatives was screened towards three representative cancer cell lines(mCF-7,A549,and HCT116).most of the evaluated derivatives showed a moderate to excellent anti-proliferative activity towards the selected cell *** these,compounds 4h,4k,10,12a,and 12b showed both potent anticancer activity(ICs0m)and lower cytotoxic effect(ICs0>58μm)on non-tumorigenic cells(mCF-10A and NCm460),suggesting their promising potential to be lead molecules for future antitumor drug *** structure-activity relationships have been also ***,quantum chemical studies based on Density Functional Theory(DFT)of the synthesized compounds were investigated and found to be consistent with the in vitro inhibitory activities.

关键词： pyridine nitrile synthesis