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low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun liu Yiren Yu Guoshu Gao Yumeng Zhao Xiongfu Zhang Guodong liu Guohui yang State Key laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology State Key laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. by optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 l highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： MFI zeolite ZSM-5 Nanosheets Scale-up synthesis Aromatic alkylation

NADPH oxidase： recent evidence for its role in erectile dysfunction

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Asian Journal of Andrology 2008年第1期10卷 6-13页

作者： liming Jin arthur l.burnett Department of Urology The James Buchanan Brady Urological Institute Johns Hopkins Medical Institutions Baltimore MD 21287 USA

Important roles for reactive oxygen species （ROS） in physiology and pathophysiology have been increasingly recognized. Under normal conditions, ROS serve as signaling molecules in the regulation of cellular functions. However, enhanced ROS production as a result of the activation of nicotinamide adenine dinucleotide phosphate （NADPH） oxidase contributes significantly to the pathogeneses of vascular diseases. Although it has become evident that increased ROS is associated with erectile dysfunction （ED）, the sources of ROS in the penis remain largely unknown. In recent years, emergent evidence suggests the possible role of NADPH oxidase in inducing ED. In this review, we examine the relationship between ROS and ED in different disease models and discuss the current evidence basis for NADPH oxidase-derive＇d ROS in ED.

关键词： reactive oxygen species erectile function superoxide penis nitric oxide

INVESTIGATION ON THE FORMATION MECHANISM OF TITANIUM CARbIDE PREPARED bY IN SITU REACTION IN MOlTEN AlUMINUM

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Acta Metallurgica Sinica(English letters) 1997年第6期10卷 485-488页

作者： yang, b. Wang, Y.Q Zhang, J. Zhou, b.l. Inst of Metal Research Chinese Acad of Sciences Shenyang China

A novel technique in which TiC particulate are prepared by an in situ reaction in molten aluminum was introduced for producing TiC/Al composite. In order to reveal the characteristics of the technique, the formation mechanism of TiC particulate prepared by this method was studied. both theoretical and experimental results show that the TiC particulate is formed by a diffusion mechanism when the molar fraction of aluminum in the preforms is higher than 20.02%. On the contrary, the TiC particulate is formed by a solution-precipitation mechanism when the fraction of aluminum in the preforms is lower than 20.02%.

关键词： Aluminum metallurgy In situ processing Metallic matrix composites Titanium carbide

A novel approach to enhance decrepitation temperature and reducibility of ultrafine iron ore concentrate pellets

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Journal of Iron and Steel Research International 2024年第11期31卷 2622-2632页

作者： b.l.Wen Z.H.Fan J.X.li D.l.liu J.l.yang School of Metallurgical Engineering Anhui University of TechnologyMa'anshan 243032AnhuiChina Jianlong(liaoning)Energy Saving and Environmental Protection

Utilizing ultrafine iron ore concentrate for pellet production can expand domestic iron ore resources in China and promote the utilization of low-grade ***,a challenge arises with the low decrepitation temperature and reducibility in the preparation process of ultrafine iron ore concentrate *** address the challenge,a novel approach was proposed,which incorporated straw powder as an additive to enhance pellet porosity,thereby improving the decrepitation temper-ature and reducibility of ultrafine iron ore concentrate *** effect of varying proportions of straw powder(0.0-2.0%)on the characteristics of ultrafine iron ore concentrate pellets was *** indicate that at a 2.0%straw powder ratio,pellet decrepitation temperature notably rises from 380 to 540℃,while the reducibility index escalates from 25.7%to 48.1%.Nevertheless,the addition of straw powder results in diminished drop strength,compressive strength of green pellets,and cold crushing strength of fired *** addition,enhanced pellet reducibility leads to exacerbated reduction swelling index and reduction degradation *** these effects,all parameters remain within an acceptable range.

关键词： Ultrafine iron ore concentrate:Straw powder Green pellet quality Decrepitation temperature:Metallurgical property

Achieving ultrahigh electromechanical properties with high TC in PNN-PZT textured ceramics

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Journal of Materials Science & Technology 2024年第8期175卷 258-265页

作者： Q.Wang l.bian K.li Y.C.liu Y.l.yang b.yang W.W.Cao School of Instrumentation Science and Engineering Harbin Institute of TechnologyHarbin 150080China Guangdong Provincial Key laboratory of Electronic Functional Materials and Devices Huizhou UniversityHuizhou 516001China Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150080China

textured Pb(Ni_(1/3)Nb_(2/3))O_(3)-PbZrO_(3)-PbTiO_(3)(PNN-PZT)ceramics were prepared by templated grain growth(TGG)technique using 0.36PNN-x PZ-(0.64-x)PT(x=0.23,0.25 and 0.27)powder *** template content was derived to achieve the best electromechanical properties of textured *** piezoelectric coefficient d33=1165 pC/N,Curie temperature T_(C)=197℃,longitudinal mode electrome-chanical coupling factor k33=0.86 and a very large effective piezoelectric strain coefficient d_(33)^(*)=2041 pm/V were simultaneously achieved at the morphotropic phase boundary(MPb)composition(x=0.25)with 3 vol.%baTiO_(3)(bT)*** structures of textured ceramics were analyzed in detail to reveal the origin of these high piezoelectric and electromechanical properties.

关键词： Pb(Ni_(1/3)Nb_(2/3))O_(3)-PbZrO_(3)-PbTiO_(3)(PNN-PZT) ceramics MPb composition Texture engineering Electromechanical properties Domain structure

Generation of Electron Traps at High Field in Silicon Oxide Films

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Chinese Physics letters 1995年第7期12卷 420-423页

作者： b.l.yang H.Wong Y.C.Cheng Department of Electronic Engineering City University of Hong KongTat Chee AvenueKowloonHONG KONG

Temperature dependences of the high-field electron trapping in a SiO_(2) thin film for temperature ranging from 100 to 423K are *** is found that in the investigated temperature range,when the temperature decreases the effective surface density of the electron traps in the film decreases;the energy levels of the effective electron traps at high field concentrate at very narrow energy *** thermal generation rate is found to be 1.283x10^(10)/cm^(2).K and its activation energy is *** on these results,a model for the electron traps generated at high field in thin oxide is proposed.

关键词： film Electron energy

Pseudo-Depth/Intercept-Time Monotonicity Requirements in the Inverse Scattering Algorithm for Predicting Internal Multiple Reflections

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Communications in Computational Physics 2009年第1期5卷 163-182页

作者： bogdan G.Nita arthur b.Weglein Department of Mathematical Sciences Montclair State University1 Normal AvenueMontclairNJ 07043USA. Department of Physics University of Houston617 Science and Research Bldg.1HoustonTX 77004USA

In this paper we discuss the inverse scattering algorithm for predicting internal multiple reflections(reverberation artefacts),focusing our attention on the construction *** speaking,the algorithm combines amplitude and phase information of three different arrivals(sub-events)in the data set to predict one multiple *** three events are conditioned by a certain relation which requires that their pseudo-depths,defined as the depths of their turning points relative to the constant background velocity,satisfy a lower-higher-lower *** implicitly assumes a pseudo-depth monotonicity condition,i.e.,the relation between the actual depths and the pseudo-depths of any two sub-events is the *** study this relation in pseudo-depth and show that it is directly connected with a similar relation between the vertical or intercept times of the *** paper also provides the first multidimensional analysis of the algorithm(for a vertically varying acoustic model)with analytical *** show that the construction of internal multiples is performed in the plane waves domain and,as a consequence,the internal multiples with headwaves sub-events are also predicted by the *** we analyze the differences between the time monotonicity condition in vertical or intercept time and total travel time and show a 2D example which satisfies the former but not the *** we discuss one case in which the monotonicity condition is not satisfied by the sub-events of an internal multiple and discuss ways of lowering these restrictions and of expanding the algorithm to address these types of multiples.

关键词： Multiple reflections seismic imaging inverse scattering

Ageing and brugada syndrome: considerations and recommendations

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Journal of Geriatric Cardiology 2013年第1期10卷 75-81页

作者： Pieter G. Postema Hanno l Tan arthur AM Wilde Department of Cardiology Heart Center Academic Medical Center University of Amsterdam P.O. box 22660 1100 DD Amsterdam The Netherlands Princess Al-Jawhara Al-brahim Centre of Excellence in Research of Hereditary Disorders Jeddah Kingdom of Saudi Arabia

brugada syndrome is an inherited disease associated with an increased risk of lethal ventricular arrhythmias. Such arrhythmias stem from innate disruptions in cardiac electrophysiology. Typically, such arrhythmias occur in the third or fourth decade of life. However, brugada syndrome may also affect geriatric patients. In this paper, we focus on the ageing patientwithbrugada syndrome, and specifically, on the interaction between brugada syndrome and the more usually acquired clinical problems that may occur with increasing age, such as the use of cardiovascular and non-cardiovascular drugs, or the need for surgery. Such common conditionsmay also disrupt cardiac electrophysiology, thereby conferring added risk for brugada syndrome patients. We present some considerations and recommendations that may serve as guidance to address these complexities.

关键词： Aging Arrhythmias brugada syndrome Geriatrics Risk stratification Sudden death

Modified malleable prosthesis with a fixed mesh:case series for the Ghattas technique

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Asian Journal of Andrology 2022年第2期24卷 167-170页

作者： Osama Ghattas Mohamed Fahmy Doheim Hossam Kotb arthur l burnett Dar-elzokora Center of Andrology Alexandria 21500Egypt Alexandria Faculty of Medicine Alexandria UniversityAlexandria 21131Egypt Department of Urology Johns Hopkins University School of MedicineBaltimoreMD 21287USA

Penile prosthetic implantation represents a cornerstone for patients with organic erectile dysfunction(ED)that is refractory,unsatisfactory,or contra-indicated for other approved medical or mechanical *** this study,we introduce the“Ghattas technique,”wherein we constructed a polypropylene mesh sheath that surrounds and is fixed to a 13-mm malleable prosthesis cylinder,which can increase the cylinder diameter for cases that need a larger *** patients underwent preoperative evaluation and completed the five-item International Index of Erectile Function questionnaire(IIEF-5).Postoperative outcomes were evaluated by IIEF-5 and Erectile Dysfunction Inventory of Treatment Satisfaction(EDITS)questionnaires at final *** mean age of the 23 included patients was 57.9(standard deviation[s.d.]:11.4)years and the mean duration of ED was 8.5(s.d.:7.9)*** improvement was determined by comparing mean preoperative and postoperative IIEF-5 scores(8.3[s.d.:3.9]vs 24.6[s.d.:0.6],Plarger than 13 *** studies are needed to confirm these results.

关键词： erectile dysfunction mesh penile prosthesis surgical technique