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Chinese Journal of Chemical Engineering 2018年第5期26卷 1012-1021页

作者： muhammad Sarfraz m. ba-Shammakh Department of Polymer and Process Engineering University of Engineering and Technology Lahore 54890 Pakistan Department of Chemical Engineering King Fahd University of Petroleum and Minerals Dhahran 31261 Saudi Arabia

Water stable mixed-matrix membranes(mmms) were developed to help control the global warming by capturing and sequestrating carbon dioxide(CO_2) from post-combustion flue gas originated from burning of fossil *** of different compositions were prepared by doping glassy polymer Ultrason? S 6010(US) with nanocrystals of zeolitic imidazolate frameworks(ZIF-300) in varying degrees. Solution-casting technique was used to fabricate various mmms to optimize their CO_2 capturing performance from both dry and wet gases. The prepared composite membranes indicated enhanced filler-polymer interfacial adhesion, consistent distribution of nanofiller, and thermally established matrix configuration. CO_2 permeability of the membranes was enhanced as demonstrated by gas sorption and permeation experiments performed under both dry and wet conditions. As compared to neat Ultrason? membrane, CO_2 permeability of the composite membrane doped with 40 wt% ZIF-300 nanocrystals was increased by four times without disturbing CO_2/N_2 ideal selectivity. In contrast to majority of previously reported membranes, key features of the fabricated mmms include their structural stability under humid conditions coupled with better and unaffected gas separation performance.

关键词： Hydrophobic mmms ZIF-300 Gas permeation CO2 capture Permselectivity

Enzymatic Synthesis of Polycaprolactone:Effect of Immobilization mechanism of CALB on Polycaprolactone Synthesis

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Journal of Renewable materials 2018年第6期6卷 619-629页

作者： Yasemin Kaptan.m.Sc Yüksel Avcıbaşı-Güvenilir Istanbul Technical University Department of Chemical EngineeringIstanbul Technical University34469Maslak-Istanbul

Surface-modified rice husk ash was used as an inorganic support material for immobilization of Candida antarctica lipase B.(3-aminopropyl)trimethoxysilane was used for surface *** of CALB was performed via both physical adsorption and *** synthesis was carried out by using these immobilized enzymes,free enzyme and Novozyme 435®.molecular weight distribution of polymer samples was obtained by gel permeation chromatography(GPC)and chain structures of the polymer samples were observed by hydrogen nuclear magnetic resonance(1H-NmR).The highest monomer conversion is generally obtained by using cross-linked enzyme,around 90%.PDI values for all polymer samples were approximately 1.5 which can be considered as *** general cross-linked enzymes were better than physically adsorbed enzymes in terms of average molecular *** can be concluded that PCL can be synthesized with these immobilized enzymes with high molecular weight and low PDI values.

关键词： Candida antarctica lipase B cross-linking physical adsorption Polycaprolactone rice husk ash

Influence of cerium ions on structure-dependent magnetic properties of ba-Sr m-type hexaferrite nanocrystals

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Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： Ram A.Pawar Sunil m.Patange P.m.Dighe Sher Singh meena Abdullah GAl-Sehemi mehboobali Pannipara Santosh S.Jadhav Department of Physics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Department of Physics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia Padmashri Vikhe Patil College of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia Solid State Physics Division Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Department of Chemistry King Khalid UniversityAbha61413Saudi Arabia Department of Physics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The present study is a systematic effort to investigate the structure-sensitive magnetic parameters of Ce^(3+) substituted ba-Sr hexaferrite nanocrystals chemically formulated as ba_(0.5)Sr_(0.5)Ce_(x)Fe_(12-x)O_(19) where x=0.0-0.2 with Δx=*** hexaferrite powders were prepared using the sol-gel self-ignition route and structurally characterized by means of powder X-ray diffraction and Fourier transform infrared *** creation of the m-type hexaferrite phase within the synthesized samples was revealed from the Rietveld refinement of the X-ray *** occurrence of a secondary phase of CeO_(2) was revealed within the hexaferrites for the substitution,x> *** refined X-ray diffraction data were utilized to compute the lattice parameters,X-ray density,and lattice parameter *** crystal structure plotted from the refined XRD data reveals the occupancy of the ions at different lattice *** XPS data of the hexaferrite were analyzed to confirm the oxidation states of the constituent *** nanocrystalline nature of the hexaferrites was revealed from the crystallite sizes calculated using Scherer's *** analysis of FTIR spectra confirms that only a fraction of Ce^(3+)accommodated in the lattice and the remaining Ce content reside in the form of the CeO_(2) *** morphology of the hexaferrites was analyzed from the FESEm profiles of the ferrite *** magnetic behavior study was performed by analyzing the Curie temperature,hysteresis loops,and hyperfine interactions by means of susceptibility,V.S.m,and mossbauer spectroscopy,*** hexaferrites with increasing coercivity,decreasing saturation magnetization,and decreasing Curie temperature are reported in the *** substituted Ce^(3+)ions inhibit the grain growth and create lattice imperfections giving rise to hexaferrites with tuned magnetic parameters suitable for different applications.

关键词： ba-Sr hexaferrite Ce^(3+)substitution XPS Saturation magnetization Coercivity m?ssbauer spectroscopy

Increased syndecan-1 and glypican-3 predict poor perinatal outcome and treatment resistance in intrahepatic cholestasis

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Hepatobiliary & Pancreatic Diseases International 2020年第3期19卷 271-276页

作者： basak Gümüs Güler Sibel Ozler Department of Health Sciences Istinye UniversityIstanbul 34010Turkey Department of Perinatology Selcuk University Faculty of MedicineKonya 42130Turkey

background:Intrahepatic cholestasis of pregnancy(ICP)increases the risk of adverse pregnancy *** study aimed to explore the association between serum syndecan-1 and glypican-3 levels and the adverse perinatal outcome as well as the responses to the treatment of ursodeoxycholic acid(UDCA).methods:This prospective,case control study included 88 pregnant women(44 women with ICP and 44 healthy controls).The primary end points were the perinatal outcome and the response to UDCA therapy.A logistic regression model was used to identify the independent risk factors of adverse pregnancy outcomes and reduced response to UDCA ***:Women with ICP had significantly higher serum syndecan-1(1.27±0.36 ng/m L vs.0.98±0.50 ng/m L;P=0.003),glypican-3(1.78±0.13 ng/m L vs.1.69±0.16 ng/m L;P=0.004),AST(128.59±1.44 vs.13.29±1.32 U/L;Pmpared with the *** increased levels of syndecan-1(OR=4.715,95%CI:1.554–14.310;P=0.006),glypican-3(OR=8.465,95%CI:3.372–21.248;P=0.007),ALT(OR=1.382,95%CI:1.131–1.690;P=0.002),and postprandial bile acid(Pba)(OR=3.392,95%CI:1.003–12.869;P=0.026)were correlated to *** adverse neonatal outcome was related to increased glypican-3(OR=4.275,95%CI:2.726–5.635;P=0.039),and Pba(OR=3.026,95%CI:1.069–13.569;P=0.037).Increases of syndecan-1(OR=7.464,95%CI:2.130–26.153,P=0.017)and glypican-3(OR=6.194,95%CI:2.951–13.002;P=0.025)were the risk factors of decreased response to UDCA ***:Syndecan-1 and glypican-3 might be powerful determinants in predicting adverse perinatal outcome in patients with ICP,and they can be used to predict the response to the UDCA treatment.

关键词： Intrahepatic cholestasis of pregnancy Syndecan-1 Glypican-3 Adverse perinatal outcome Response to UDCA

The effect of propagation delay on the dynamic evolution of the Bitcoin blockchain

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Digital Communications and Networks 2020年第2期6卷 157-166页

作者： moustapha ba mODAL’X(Laboratoire de modélisation aléatoire)of UniversitéParis Nanterre(Paris X) MODAL’X is the Mathematics and Computer Sciences laboratory of UniversitéParis Nanterre(Paris X)ministerial label EA 3454UFR SEGMIdépartement Mathématiques-Informatique200 avenue de la République92000NanterreFrance

This paper analyzes the selfish-mine strategy in the Bitcoin blockchain introduced in 2013 by *** and *** strategy could be used by a colluding pool of miners to earn more than their fair share of the mining revenue and in consequence to force other honest miners to join them to decrease the variance of their revenues and make their monthly revenues more *** is a very dangerous dynamic that could allow the rogue pool of miners to go toward a majority by accumulating powers of news adherents and control the entire *** that the propagation delay of information between any two miners in the network,which is not negligible and follows a normal distribution with mean proportional to the physical distance between the two miners,and a constant variance independent of others'delays,we prove that no guarantee can be given about the success or failure of the selfish-mine attack because of the variability of information propagation in the network.

关键词： Blockchain Bitcoin mining Selfish-mine attack Propagation delay of information

移植物厚度对角膜内皮失代偿行简易后弹力层角膜内皮移植效果的影响

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中国组织工程研究 2025年第6期29卷 1199-1207页

作者：巴颜红高明宏陈颖欣中国人民解放军北部战区总医院辽宁省沈阳市110000

背景:研究表明较薄移植物视力恢复更快、排斥风险更低,国内缺乏对内皮移植术后不同植片厚度的临床疗效分析,因此,确定最佳移植物厚度对于提高手术疗效至关重要。目的:评价简易后弹力层剥离内皮角膜移植术后不同植片厚度对视力恢复及其... 详细信息

背景:研究表明较薄移植物视力恢复更快、排斥风险更低,国内缺乏对内皮移植术后不同植片厚度的临床疗效分析,因此,确定最佳移植物厚度对于提高手术疗效至关重要。目的:评价简易后弹力层剥离内皮角膜移植术后不同植片厚度对视力恢复及其他预后指标的影响。方法:选取2013年1月至2023年2月在北部战区总医院接受简易后弹力层剥离内皮角膜移植手术治疗的角膜内皮失代偿患者共72例(72眼),其中薄植片组(m)32例(32眼),厚植片组(≥100μm)40例(40眼)。随访1年,观察两组术前及术后1,3,6,12个月的最佳矫正视力,术后1年角膜内皮细胞数、角膜植片透明度、术后并发症、植片生存情况。结果与结论:①两组患者术后视力较术前均有显著提高,薄植片组患者术后3个月最佳矫正视力优于厚植片组(P0.05);③两组患者继发性青光眼、植片免疫排斥、植片移位等术后并发症发生率比较差异无显著性意义(P>0.05);④两组术后1年植片生存率比较差异无显著性意义(93.8%,92.3%,P>0.05);⑤结论:简易后弹力层剥离内皮角膜移植术是一种安全有效的角膜内皮移植手术方式,其术后疗效与传统后弹力层剥离内皮角膜移植术相似,而且植片植入方式更为简便。较薄植片能够更早提供最佳矫正视力,更早完成角膜重塑,因此在治疗角膜内皮失代偿疾病时,优先选择薄移植物来提高恢复时间。

关键词：后弹力层撕除角膜内皮移植术角膜内皮失代偿继发性青光眼植片移位原发移植失败植片排斥角膜内皮细胞数角膜移植

Characterization of Arithmetic Functions that Preserve the Sum-of-squares Operation

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Acta mathematica Sinica,English Series 2014年第4期30卷 689-695页

作者： Bojan baI Department of mathematics and Informatics University of Novi Sad

We characterize all functions f ： N → C such that f（m^2 ＋ n^2） = f（m）^2 ＋ f（n）^2 for all m, n ∈ N. It turns out that all such functions can be grouped into three families, namely f ≡ 0, f（n） = ±n （subject to some restrictions on when the choice of the sign is possible） and f（n） =±l/2（again subject to some restrictions on when the choice of the sign is possible）.

关键词： Arithmetic function functional equation sum of squares

Influence of Solid Fraction on Gravity Segregation of Sn in A1-20Sn Alloy Casting

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Journal of materials Science & Technology 2000年第6期16卷 577-580页

作者： Zhang, P. Du, Y.H. Zeng, D.B. Cui, J.Z. ba, L.m. Dep. of mechanical Eng. Tsinghua Univ. Beijing 100084 China

The influence of solid fraction of Al-20Sn alloy mushy on gravity segregation of Sn in casting was studied . The relationship between solid fraction and the temperature of alloy mushy and that between solid fraction of alloy mushy and size of Sn particle in ingot were determined. The results show that the relationship between solid fraction and the temperature of alloy mushy was fs=1683-4.86t+0.003 5t2. The extent of gravity segregation of Sn in casting reduced gradually with the increase of solid fraction of alloy mushy. When solid fraction of alloy mushy was larger than 40%, the gravity segregation of Sn in casting could be removed basically, and the relationship between solid fraction of alloy mushy and size of Sn particle in ingot was s=-0.64fs+70.8.

关键词： metal casting

Chemical Defense of Soft Coral Sinularia polydactyla from the Red Sea Against marine Biofilm-Forming bacteria

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Journal of Ocean University of China 2018年第6期17卷 1451-1457页

作者： ESKandER Rehab AL-SOFYANI Abdulmohsin A. EL-SHERBINY mohsen m.O. ba-AKDAH mohammad Abdulaziz SATHEESH Sathianeson Department of marine Biology Faculty of Marine Sciences King Abdulaziz University

Soft corals are an important group of organisms that live in reef ecosystems. In this study, the chemical defense of soft coral Sinularia polydactyla against biofilm-forming bacteria was assessed. The soft coral S. polydactyla was collected from the Obhur creek of the Red Sea and the bioactive compounds were extracted under different conditions using methanol and hexane as solvents. Results revealed that the bioactive compounds produced by the soft coral S. polydactyla were active against the growth, hydrophobicity and extracellular polymeric substances production of the biofilm-forming bacteria. However, the damage or injury in soft coral tissue caused a decrease in the activity against biofilm-forming bacteria. GC-mS analysis revealed that sesquiterpenes were abundant in normal coral sample extract while cembranoids were abundant in damaged coral sample extracts. In general, the results indicated that the soft corals either under stress or with damage may not have a strong chemical defense against the colonizing marine organisms and competitors.

关键词： chemical ecology antifouling antibiofilm activity bioactive compound coral tissue damage

Zircon and monazite Ages Constraints on Devonian magmatism and Granulite-Facies metamorphism in the Southern Qaidam Block:Implications for Evolution of Proto-and Paleo-Tethys in East Asia

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Journal of Earth Science 2018年第5期29卷 1132-1150页

作者： Jin ba Lu Zhang Chuan He Neng-Song Chen Timothy m.Kusky Qinyan Wang Yusheng Wan Xiaoming Liu School of Earth Sciences China University of GeosciencesWuhan 430074China College of Earth Science Chengdu University of TechnologyChengdu 610059China Sichuan Institute of Geological Survey Chengdu 610081China Center for Global Tectonics China University of GeosciencesWuhan 430074China Beijing SHRImP Center Beijing 100037China State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an 710069China

High-temperature magma generation process and granulite-facies metamorphism can provide important information about mantle-crustal interaction and tectonic evolution. The strongly peralu- minous monzonite pluton, the Jinshuikou cordierite granite on the southern margin of the Qaidam Block, can provide important information about the mantle-crustal interaction and constraints on tectonic tran- sition from Proto-Tethys to Paleo-Tethys. This pluton develops enclaves of mafic granulite, amphibolite and quartzofeldspathic rocks, and is cut by massive monzonitic leuco-granite veins. Zircon and monazite U-Pb dating for the cordierite granite, the granulite enclaves and a massive monzonitic leuco-granite vein reveal that the cordierite granitic magma was generated from mesoproterozoic continental crust with protolith derived from a provenanee that was composed of 〉2.8 Ga old recycled crustal materials and re- corded a -1.7 Ga magmatic event. The continental crust underwent low-pressure granulite-facies metamorphism at -380 ma ago, whereas the cordierite granite magmas was generated and emplaced during 380 ma, followed by intrusion of the massive monzonitic leuco-granite vein at circa 370-330 ma. These data suggest that after the final closure of Proto-Tethys Ocean spreading along the southern Qaidam Block at -420 ma, break-off of the subducted slab or delamination of the lower crustal base and upwelling of the asthenospheric mantle beneath the southern Qaidam Block occurred before the mid-Devonian, and that the initiation of the Paleo-Tethys tectonics might initiate near the end of Early-Carboniferous in the East Kunlun-Qaidam region, East Asia.

关键词： zircon and monazite U-Pb geochronology cordierite peraluminous granite low pressure granulite Proto- and Paleo-Tethys evolution East Kunlun-Qaidam.