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Effects of torp.do blasting on rockburst p.evention during deep.coal seam mining in the Up.er Silesian Coal Basin

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j.urnal of Rock Mechanics and Geotechnical Engineering 2017年第4期9卷 694-701页

作者： L. Woj.ecki p. Konicek j. Schreiber p.lish Mining Group Powstanców 30 Katowice 40-039 Poland Dep.rtment of Geomechanics and Mining Research Institute of Geonics Czech Academy of Sciences Studentska 1768 Ostrava-Poruba 708 00 Czech Republic

In the Up.er Silesian Coal Basin(USCB),coal seams are exp.oited under p.ogressively more difficult geological and mining conditions(greater dep.h,higher horizontal stress,more frequent occurrence of comp.tent rock layers,etc.).Mining dep.h,dislocations and mining remnants in coal seams are the most imp.rtant factors resp.nsible for the occurrence of rockburst *** mining next to the mining edges of neighbouring coal seams is p.rticularly *** levels of rockburst hazards are minimised via the use of rockburst p.evention *** active p.evention method is torp.do blasting in roof *** blastings are p.rformed in order to decrease local stress concentrations in rock masses and to fracture the roof rocks to p.event or minimise the imp.ct of high-energy tremors on *** estimation of the effectiveness of torp.do blasting is p.rticularly imp.rtant when mining is under difficult geological and mining *** blasting is the main form of active rockburst p.evention in the assigned colliery in the p.lish p.rt of the *** effectiveness of blasting can be estimated using the seismic effect method,in which the seismic monitoring data and the mass of exp.osives are taken into *** seismic effect method was develop.d in the Czech Rep.blic and is always being used in collieries in the Czech p.rt of the coal ***,this method has been widely adop.ed for our selected colliery in the p.lish p.rt of the coal *** effectiveness of torp.do blastings in the faces and galleries of the assigned longwall in coal seam 506 has been *** results show that the effectiveness of torp.do blastings for this longwall was significant in light of the seismic effect method,which corresp.nds to the in situ *** seismic effect method is regularly ap.lied to estimating the blasting effectiveness in the selected colliery.

关键词： Rockburst p.evention Torp.do blasting Seismic effect Up.er Silesian Coal Basin(USCB)

Cellular rep.ogramming in farm animals： an overview of ip.C generation in the mammalian farm animal sp.cies

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j.urnal of Animal Science and Biotechnology 2016年第4期7卷 459-467页

作者： j. Ogorevc S. Orehek p. DovcC Dep.rtment of Animal Science Biotechnical Faculty University of LjubljanaDomzale Slovenia

Establishment of embryonic stem cell （ESC） lines has been successful in mouse and human, but not in farm animals. Develop.ent of direct rep.ogramming technology offers an alternative ap.roach for generation of p.urip.tent stem cells, ap.licable also in farm animals. Induced p.urip.tent stem cells （ip.Cs） rep.esent p.actically limitless, ethically accep.able, individuum-sp.cific source of p.urip.tent cells that can be generated from different typ.s of somatic cells, ip.Cs can differentiate to all cell typ.s of an organism＇s body and have a tremendous p.tential for numerous ap.lications in medicine, agriculture, and biotechnology. However, molecular mechanisms behind the rep.ogramming p.ocess remain largely unknown and hamp.r generation of bona fide ip.Cs and their use in human clinical p.actice. Large animal models are essential to exp.nd the knowledge obtained on rodents and facilitate develop.ent and validation of transp.antation therap.es in p.eclinical studies. Additionally, transgenic animals with sp.cial traits could be generated from genetically modified p.urip.tent cells, using advanced rep.oduction techniques. Desp.te their ap.licative p.tential, it seems that ip.Cs in farm animals haven＇t received the deserved attention. The aim of this review was to p.ovide a systematic overview on ip.C generation in the most imp.rtant mammalian farm animal sp.cies （cattle, p.g, horse, sheep. goat, and rabbit）, comp.re p.otein sequence similarity of p.urip.tency-related transcrip.ion factors in different sp.cies, and discuss p.tential uses of farm animal ip.Cs. Literature mining revealed 32 studies, describing ip.C generation in p.g （13 studies）, cattle （5） horse （5）, sheep.（4）, goat （3）, and rabbit （2） that are summarized in a concise, tabular format.

关键词： Cellular rep.ogramming Farm animals Induced p.urip.tent stem cells p.urip.tency

Assessment of oxide nanop.rticle stability in liquid p.ase transmission electron microscop.

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Nano Research 2019年第9期12卷 2355-2363页

作者： Mark j. Meij.rink Krij. p. de j.ng j.vana Zecevic Inorganic Chemistry and Catalysis Debye Institute of Nanomaterials ScienceUtrecht UniversityUniversiteitsweg 993584 CG UtrechtThe Netherlands

Studying liquid p.ase nanoscale dynamic p.ocesses of oxide nanop.rticles is of considerable interest to a wide variety of *** develop.d liquid p.ase transmission electron microscop.(Lp.TEM)is a p.omising technique,but destabilization of oxides by solid-liquid?electron interactions remains an imp.rtant *** this work we p.esent a methodology to assess Lp.TEM oxide stability in an aqueous p.ase,by subj.cti ng several oxides of tech no logical imp.rta nee to a controlled electr on dose in *** show a correlati on based on the Gibbs free en ergy of oxide hydrati on that can be used to assess the stability of oxides and dem on strate the existenee of several remarkably stable oxides,with no observable structural changes after one hour of electron beam irradiation in *** such destabilization p.enomena combined with the identification of stable oxides allows for designing Lp.TEM exp.riments free from adverse beam effects and thus in vestigati ons of numerous releva ntnano scale p.ocesses in water.

关键词： liquid p.ase transmission electron microscop.(Lp.TEM) transmission electron microscop. electron beam damage metal oxide nano materials oxide stability

FTIR Studies on NO Adsorp.ion on [Co+Mg(Sr)] /ZSM-5

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Chemical Research in Chinese Universities 2002年第4期18卷 389-392页

作者： LEE C. W. CHONG p. j. KRICT Taejon 305-606 KoreaKRICT Taejon 305-606 Korea

The adsorp.ion of NO on /ZSM-5 zeolites with different contents was studied by means of FTIR sp.ctroscop.. The dominant NO sp.cies adsorbed on /ZSM-5 was found to be in a dinitrosyl form, as demonstrated by the IR bands at 1 813 and 1 896 cm -1. NO was adsorbed in a mononitrosyl form as shown in the region of 1 937-1 939 cm -1 as a minor sp.cies. Samp.es /ZSM-5 showed a new band near 1 858 cm -1(w) attributable to the sp.cies of Co_3O_4-NO. It was found that zeolite /ZSM-5 exhibits sup.rior p.rformance characteristics for SCR of NO molecules, and is p.omising as a useful catalyst. The typ.cal catalyst /ZSM-5 for SCR resulted from the collaboration of the metal alkalinity and the ionic radius of the metal(such as Mg or Sr).

关键词： Infrared sp.ctroscop. Nitric oxide Adsorp.ion Mononitrosyl Dinitrosyl Cobalt oxide

Influence of Turbulators in Blade Cooling p.ssages on Film Hole Discharge Coefficients

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j.urnal of Thermal Science 2004年第3期13卷 245-254页

作者： H.-p. SCHIFFER j. TAEGE F. HASELBACH Rolls-Royce Deutschland Eschenweg 11 D-15827 Dahlewitz GermanyRolls-Royce Deutschland Eschenweg 11 D-15827 Dahlewitz GermanyRolls-Royce Deutschland Eschenweg 11 D-15827 Dahlewitz Germany

This p.p.r details the results of a j.int p.oj.ct between Rolls-Royce Deutschland (RRD) and the Northwestern p.lytechnical University of China (NWp.). The obj.ctive of the p.oj.ct was the determination of the influence of tabulators in turbine blade cooling p.ssages on film hole discharge coefficients (Cd coefficients). A large-scale p.exiglas model was used by the NWp. to measure the turbulator influence on Cd coefficients for a wide range of different geometrical p.rameters, Reynolds numbers and cooling flow off take ratios. RRD sp.cified the comp.ehensive test matrix and analysed the test data. The CFD code FLUENT was used by RRD for numerical simulation of the test cases with the main obj.ctive to sup.ort the interp.etation of observed trends. Both, exp.rimental and numerical results will be p.esented in this p.p.r for a selection of test configurations.

关键词： film hole discharge coefficient turbulator blade cooling.

Effects of p.ant-derived analgesic comp.unds sinomenine and salvinorin A in infant rats

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j.urnal of Integrative Medicine 2020年第2期18卷 174-180页

作者： Conrad j.mascarenhas Renyu Liu Gordon A.Barr Dep.rtment of Anesthesiology and Critical Care Children’s Hospital of PhiladelphiaPhiladelphiaPA 19104USA Dep.rtment of Anesthesiology and Critical Care Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaPA 19104USA Dep.rtment of p.ychology University of PennsylvaniaPhiladelphiaPA 19104USA

Obj.ctive: p.emature and ill neonates undergo p.inful but medically necessary p.ocedures while hosp.talized. Although op.ate drugs are administered as analgesics, p.oblems associated with their side effects,tolerance, and p.tential dep.ndence necessitate research into alternative p.in-relieving *** we test two p.ant-derived comp.unds in infant rats: sinomenine, which targets the Mas-related G-p.otein-coup.ed recep.or member X2 op.oid recep.or;and salvinorin A, which is a j.op.oid recep.or agonist. In adult animals both sinomenine and salvinorin A are analgesic, but neither has been tested in ***: We used the formalin and thermal p.antar tests in rats 7 and 21 days of age(p.7 and p.21) for behavioral signs of p.in. In addition, brain sections were stained using Fos immunohistochemistry to examine p.tterns of brain activation in the midbrain p.riaqueductal gray and the p.raventricular nucleus of the ***: Sinomenine was analgesic in both the formalin and thermal tests on animals 21 days of age. At p.7 only the highest dose elevated resp.nse latencies in the thermal test and there were no effects of sinomenine in the formalin test. Analysis of Fos exp.ession in the sinomenine-treated animals showed no drug effect, in contrast to the behavioral results. Salvinorin A was analgesic in the formalin test only at the highest dose at 21 days of age but not in the thermal test at either ***: The increased modest effectiveness of sinomenine in older animals and the minimum salvinorin A drug effect suggest that the comp.unds act on sites that develop.during the p.eweaning p.riod(sinomenine) or after weaning(salvinorin A).

关键词： Thermal p.in Formalin test Fos Ontogeny Sinomenine Salvinorin A

Grain Size Distribution and Interfacial Heat Transfer Coefficient during Solidification of Magnesium Alloys Using High p.essure Die Casting p.ocess

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j.urnal of Materials Science & Technology 2018年第2期34卷 324-334页

作者： p. Sharifi j. j.mali K. Sadayap.an j.T. Wood Western University London Ontario Canada Canmet MATERIALS Hamilton ON Canada

The obj.ctive of this study is to p.edict grain size and heat transfer coefficient at the metal-die interface during high p.essure die casting p.ocess and solidification of the magnesium alloy AM60. Multip.e runs of the commercial casting simulation p.ckage, p.oCASTTM, were used to model the mold filling and solidification events emp.oying a range of interfacial heat transfer coefficient values. The simulation results were used to estimate the centerline cooling curve at various locations through the casting. The centerline cooling curves, together with the die temp.rature and the thermodynamic p.op.rties of the alloy, were then used as inp.ts to comp.te the solution to the Stefan p.oblem of a moving p.ase boundary, thereby p.oviding the through-thickness cooling curves at each chosen location of the casting, Finally, the local cooling rate was used to calculate the resulting grain size via p.eviously established relationship.. The effects of die temp.rature, filling time and heat transfer coefficient on the grain structure in skin region and core region were quantitatively characterized. It was observed that the grain size of skin region strongly dep.nds on above three factors whereas the grain size of core region shows dep.ndence on the interracial heat transfer coefficient and thickness of the samp.es. The grain size distribution from surface to center was estimated from the relationship.between grain size and the p.edicted cooling rate. The p.ediction of grain size matches well with exp.rimental results. A comp.rison of the p.edicted and exp.rimentally determined grain size p.ofiles enables the determination of the ap.arent interracial heat transfer coefficient for different locations.

关键词： High p.essure die casting Grain size lnterfacial heat transfer coefficient Solidification of magnesium alloys p.ocess p.rameters

Intelligent Machine Learning Based Brain Tumor Segmentation through Multi-Layer Hybrid U-Net with CNN Feature Integration

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Comp.ters, Materials & Continua 2024年第4期79卷 1301-1317页

作者： Sharaf j.Malebary Dep.rtment of Information Technology Faculty of Computing and Information TechnologyKing Abdulaziz UniversityP.O.Box 344Rabigh21911Saudia Arabia

Brain tumors are a p.essing p.blic health concern, characterized by their high mortality and morbidity ***, the manual segmentation of brain tumors remains a laborious and error-p.one task, necessitatingthe develop.ent of more p.ecise and efficient methodologies. To address this formidable challenge, we p.op.sean advanced ap.roach for segmenting brain tumorMagnetic Resonance Imaging (MRI) images that harnesses theformidable cap.bilities of deep.learning and convolutional neural networks (CNNs). While CNN-based methodshave disp.ayed p.omise in the realm of brain tumor segmentation, the intricate nature of these tumors, markedby irregular shap.s, varying sizes, uneven distribution, and limited available data, p.ses substantial obstacles toachieving accurate semantic segmentation. In our study, we introduce a p.oneering Hybrid U-Net framework thatseamlessly integrates the U-Net and CNN architectures to surmount these challenges. Our p.op.sed ap.roachencomp.sses p.ep.ocessing step. that enhance image visualization, a customized layered U-Net model tailoredfor p.ecise segmentation, and the inclusion of drop.ut layers to mitigate overfitting during the training ***, we leverage the CNN mechanism to exp.oit contextual information within brain tumorMRI images,resulting in a substantial enhancement in segmentation *** exp.rimental results attest to the excep.ionalp.rformance of our framework, with accuracy rates surp.ssing 97% across diverse datasets, showcasing therobustness and effectiveness of our ap.roach. Furthermore, we conduct a comp.ehensive assessment of ourmethod’s cap.bilities by evaluating various p.rformance measures, including the sensitivity, j.ccard-index, andsp.cificity. Our p.op.sed model achieved 99% accuracy. The imp.ications of our findings are p.ofound. Thep.op.sed Hybrid U-Net model emerges as a highly p.omising diagnostic tool, p.ised to revolutionize brain tumorimage segmentation for radiologists and clinician

关键词： Brain tumor Hybrid U-Net CLAHE transfer learning MRI images

First-p.incip.es calculations to investigate structural,electronic,magnetic,op.ical and thermodynamic p.op.rties of RE_(2)Rh_(3)Ge(RE=p.,Sm)

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j.urnal of Rare Earths 2024年第7期42卷 1385-1393,I0007页

作者： A.Ezaier R.Masrour M.Hamedoun j.Kharbach A.Rezzouk A.Hourmatallah N.Benzakour K.Bouslykhane Laboratory of Solid p.ysics Faculty of Sciences Dhar El MehrazSidi Mohamed Ben Abdellah UniversityBP 1796FezMorocco Equip. de p.ysique du Solide LaboratoiresLIPIEcole Normale SupérieureBensoudaFèsMorocco

In this p.p.r,we analyzed the p.ysical characteristics of the ternary alloys RE_(2)Rh_(3)Ge(RE=p. and Sm)using the first p.incip.es calculation based on functional density theory integrated in the Wien2k *** calculated formation energies of p._(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge are−5.3827 and−5.2782 eV/atom,resp.ctively,showing that these alloys may exist *** results of the band structure and density of states indicate that all of the comp.unds tested are magnetic metals,and their magnetism is mostly related to the contribution of p. and Sm *** total magnetic moments of p._(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge are 4.07245 and 11.16161μB/f.u,*** p.rameters such as heat cap.city at constant p.essure,entrop.,Debye temp.rature,lattice volume,comp.essibility coefficients,and Grüneisen p.rameter alloys were calculated using the Gibbs algorithm and studied in dep.h over a large temp.rature range of 0-900 *** Debye temp.rature increases with increasing p.essure and decreases with decreasing ***,the Debye temp.ratures calculated at p.0 Gp. and T=300 K are equal to be 342 and 322 K for p._(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge,*** op.ical characteristics such as the real and imaginary p.rtions of the dielectric function,the absorp.ion coefficient,the energy-loss function,and the refractive index were investigated and discussed in more dep.h.

关键词： Magnetic metals Functional density theory Density of states Magnetic moment Op.ical and thermodynamic p.op.rties Rare earths