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Classification and assessment of rock mass parameters in Choghart iron mine using P-wave velocity

Journal of Rock mechanics and Geotechnical Engineering 2017年第2期9卷 318-328页

作者： mohammadreza Hemmati Nourani mohsen Taheri moghadder mohsen Safari Department of mining and metallurgy Yazd UniversityYazdIran Department of mining Engineering Shahid Bahonar University of KermanKermanIran Department of mining Engineering Birjand University of TechnologyBirjandIran

Engineering rock mass classification,based on empirical relations between rock mass parameters and engineering applications,is commonly used in rock engineering and forms the basis for designing rock *** basic data required may be obtained from visual observation and laboratory or field ***,owing to the discontinuous and variable nature of rock masses,it is difficult for rock engineers to directly obtain the specific design parameters *** an alternative,the use of geophysical methods in geomechanics such as seismography may largely address this *** this study,25 seismic profiles with the total length of 543 m have been scanned to determine the geomechanical properties of the rock mass in blocks Ⅰ,Ⅲ and Ⅳ-2 of the Choghart iron ***,rock joint measurements and sampling for laboratory tests were *** results show that the rock mass rating（RmR） and Q values have a close relation with P-wave velocity parameters,including P-wave velocity in field(V;).P-wave velocity in the laboratory(V;) and the ratio of V;V;(i.e.K;= V;/V;.However,Q value,totally,has greater correlation coefficient and less error than the RmR,In addition,rock mass parameters including rock quality designation（RQD）,uniaxial compressive strength（UCS）,joint roughness coefficient（JRC） and Schmidt number（RN） show close relationship with P-wave *** equation based on these parameters was obtained to estimate the P-wave velocity in the rock mass with a correlation coefficient of 91%.The velocities in two orthogonal directions and the results of joint study show that the wave velocity anisotropy in rock mass may be used as an efficient tool to assess the strong and weak directions in rock mass.

关键词： Rock mass classification P-wave velocity Q system Rock mass rating(RmR) Geophysical methods

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Production,characterization and biological activities of acidic exopolysaccharide from marine Bacillus amyloliquefaciens 3mS 2017

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Asian Pacific Journal of Tropical medicine 2017年第7期10卷 715-725页

作者： Samah A.el-Newary Abeer Y.Ibrahim mohsen S.Asker manal G.mahmoud mohamed E.el Awady Department of medicinal and Aromatic Plants Research National Research CentreDokkiCairoEgypt microbial Biotechnology Department National Research CentreDokkiCairoEgypt

Objective: To evaluate in-vitro antioxidant, anti-inflammatory and antitumor abilities against human breast adenocarcinoma(mCF7) and human prostate cancer(PC3) as well as the suppressor effect of bacterial exopolysaccharide(BAEPS) on Ehrlich ascites carcinoma(EAC). methods: In-vitro antioxidants characters of BAEPS were determined using various methods, while anti-inflammatory activity was estimated against cyclooxygenase(COX-1 and COX-2). In-vitro study, anticancer against mCF7 and PC3 were assessed by the mitochondrial dependent reduction of yellow mTT. In in-vivo study against EAC progression, mice were inoculated with EAC cells and then were orally administered BAEPS at 200 mg/kg after 24 h(equals to 0.10 of determined LD50)/10 d. Results: BAEPS was acidic exopolysaccharide contained uronic acid(12.3%) and sulfate(22.8%) with constitution of glucose, galactose and glucuronic acid in a molar ratio1.6: 1.0: 0.9, respectively, with a molecular mass of 3.76伊104 g/mol. BAEPS appeared potent antioxidant characters as free radical scavenging, oxygen reactive species scavenging and metal chelation, while its reducing power was low. BAEPS showed selective anti-inflammatory activity against COX-2 than COX-1, COX-2 selective. BAEPS exhibited potent and selective effect to breast cell cancer mCF7, the death percentage was 65.20% with IC_(50)=70 μg/m L and IC_(90)=127.40 μg/m L. BAEPS decreased counted viable EAC cells and induced non-viable cells. BAEPS improved all assessed hematological parameters. These improvements were reflected in the increasing median survival time and significant increment(Pmor activity with a good margin of safety. The anti-tumor activity of BAEPS may be due to its content from sulfated groups and uronic acids and they have antioxidant and anti-inflammatory properties.

关键词： Antioxidant Anti-inflammatory Anti-tumor Ehrlich ascites carcinoma Exopolysaccharide Bacillus amyloliquefaciens

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Physical Studies of Some Hydrazinobenzoic Acid Complexes

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Journal of materials Science & Technology 2005年第1期21卷 140-144页

作者： m.G.Abd el Wahed S.Abd el Wanees m.el Gamel S.Abd el Haleem Faculty of Science Zagazig University Zagazig EgyptFaculty of Science Zagazig University Zagazig EgyptFaculty of Science Zagazig University Zagazig EgyptFaculty of Science Zagazig University Zagazig Egypt

The stability constants of complexes of 2-hydrazinobenzoic acid and 4-hydrazinobenzoic acid with Ni (Ⅱ), Cu (Ⅱ), Zn (Ⅱ), Cd (Ⅱ), and Hg (Ⅱ) were determined potentiometricaIly at different temperatures. The thermodynamic parameters, △G0, △H0, and △S0 were calculated and proved that the complexation process is spontaneous and endothermic. The thermodynamic functions were analyzed in terms of electrostatic and non-electrostatic components and the results reveal that ionic bonds are formed between the studied ligands and metal ions. Conductometric titration was shown that the stoichiometry of the formed complexes are m:L and m:2L. The structure of the prepared solid complexes was characterized using IR, 1H NmR, 13C NmR spectroscopies as well as X-ray diffraction technique. Finally electrical conductivity of the ligands and their copper complexes was measured and shown that the ligands have a semiconductor behaviour.

关键词： Potentiometric titration Stability constants Thermodynamic parameters Structure of metal complexes

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Diffusion coefficient of vacancies and jump length of electrons in Co_(1-x)Zn_(x)Fe_(2)O_(4)ferrites

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Journal of Advanced Ceramics 2012年第2期1卷 144-149页

作者： m.el-SAADAWY Physics Department Faculty of ScienceKafrelsheikh UniversityKafrelsheikh CityEgypt

A series of polycrystalline samples of Co_(1-x)Zn_(x)Fe_(2)O_(4)where(x=0.1,0.2,0.3,0.4,0.5 and 0.6)were prepared by the usual ceramic technique.X-ray diffraction patterns confirmed the spinel cubic *** diffusion coefficients of oxygen vacancies were estimated from dc conductivity *** was noticed that the diffusion coefficient decreases with increasing Zn^(2+)*** increase of temperature increases the diffusion of lattice *** Curie temperature,lattice parameter and jump length of electrons were studied as a function of Zn^(2+)*** the correlation between the ionic radius and the radii of octahedral and tetrahedral sites,the theoretical lattice parameters were calculated and suggested cation distribution for the given ferrites was determined.

关键词： diffusion coefficient lattice parameter jump length and jump rate of vacancies Curie temperature cation distribution

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CO oxidation and 4-nitrophenol reduction over ceria-promoted platinum nanoparticles impregnated with ZSm-5 zeolite

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Journal of Rare Earths 2022年第8期40卷 1247-1254页

作者： Zeinhom m.el-Bahy mohammed T.Alotaibi Salah m.el-Bahy Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City11884CairoEgypt Department of Chemistry Turabah University CollegeTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia

Active new ceria-promoted platinum supported on ZSm-5 catalysts were prepared and characterized by X-ray diffraction(XRD),Fourier transform infrared spectra(FTIR),transform electron microscopy(TEm),temperature programmed desorption(TPD),and FTIR of CO *** samples were prepared by the incipient wetness impregnation method and calcined at 500℃.The XRD patterns and FTIR spectra prove that the zeolite framework is kept unaltered after metal *** images prove the presence of Pt nanoparticles with particle size starting from 14 to 27 *** FTIR data suggest the formation of Pt-O-Ce ***-situ FTIR of CO adsorption over reduced samples proves the presence of Pt~0 only,and no Pt^(n+)-CO species are *** prepared catalysts were tested in both oxidation reaction(CO oxidation) in the gas phase and in reduction reaction(4-nitrophenol reduction) in the aqueous ***,CO oxidation by O_(2) results in the formation of a CO_(2) peak at 2347 cm^(-1) as the only CO oxidation product in the studied frequency *** intensity of the CO_(2) peak increases after the addition of Ce,and it is 4 times higher in Pt_(1) Ce_(0.5)ZSm-5 than that in the Ce-free *** to the FTIR data and previous reports,the increase in the catalytic activity may be due to the formation of Pt-O-Ce ***,Ce-promoted Pt_(1) ZSm5 also exhibits enhanced catalytic activity towards the reduction of 4-nitrophenol to 4-aminophenol by NaBH_(4) in the aqueous *** first-order rate constant of the reduction increases ≈13 times after incorporating equal ratios of Pt and Ce(Pt_(1) Ce_(1)ZSm-5),and the activation energy(E_(a)) decreases to 40% of that in the reaction over Pt_(1) ZSm-5.

关键词： 4-Nitrophenol CO oxidation TPD-CO Platinum-cerium ZSm-5 Rare earths

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An efficient in vitro shoot regeneration through direct organogenesis from seedling-derived petiole and leaf segments and acclimatization of Ficus religiosa

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Journal of Forestry Research 2019年第3期30卷 807-815页

作者： mohsen Hesami mohammad Hosein Daneshvar mohsen Yoosefzadeh-Najafabadi Department of Horticulture Science University of Tehran KarajAlborz 14176-14418Iran Department of Horticulture Science Ramin University of Agriculture and Natural ResourcesAhwaz Khuzestan 63417-73637Iran

Prolific and rapid in vitro plant organogenesis via direct regeneration has been obtained from axenic seedling-derived petiole and leaf explants of Ficus religiosa in murashige and Skoog (mS) medium containing different concentrations of cytokinins in combination with indole-3-butyric acid (IBA). mS medium with 1.5 mg/l 6-benzylaminopurine plus 0.15 mg/l IBA produced the highest shoot induction frequency with an average of 6.26 and 10.13 shoots per leaf and petiole explants, respectively. After 4 weeks, the highest root formation frequency (96.7%), root number (5.73), and root length (4.76 cm) were with mS medium containing 2.0 mg/l IBA plus 0.1 mg/l α-naphthalene acetic acid. In addition, the effect of four sodium nitroprusside (SNP) treatments on acclimatization was also studied. Highest morphological traits such as survival rates, fresh and dry root weights as well as antioxidant enzymatic activities such as superoxide dismutase, peroxidase, and catalase was achieved with 125 ppm SNP. The α-amino acid, proline, content was highest with this treatment while the highest H2O2 (hydrogen peroxide) was in the controls. This study introduces a cost-effective, prolific, and efficient in vitro multiplication system to supply pharmaceutical and ornamental needs. It is the first report of an in vitro organogenesis protocol for F. religiosa by direct regeneration through axenic seedling-derived petiole and leaf explants, which can be efficiently employed for the utilization of active biomolecules.

关键词： In vitro culture Ficus religiosa Sodium nitroprusside Growth regulators Antioxidant enzymes Proline

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Quality of life during COVID-19 pandemic:a community-based study in Dakahlia governorate,Egypt

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Global Health Research and Policy 2022年第1期7卷 424-432页

作者： Shorouk mohsen Ragaa el-masry Olfat Farag Ali Doaa Abdel-Hady Department of Public Health and Preventive medicine Faculty of MedicineMansoura UniversityMansouraEgypt

Background:The sudden transmission of the novel coronavirus along with instant measures taken in response to the Coronavirus Disease 2019(COVID-19)pandemic caused many new challenges adversely disturbing quality of life(QoL).The objective of this study is to measure quality of life of the public during the COVID-19 pandemic and factors affecting it among ***:This is a community-based cross-sectional household study with analytic component conducted in an agricultural area in Dakahlia governorate,Egypt and included 500 *** were collected through a structured interview,and the collected data included socio-demographic characteristics as well as some data related to their habits and comorbidities,their experience with COVID-19 and data about QoL using the COV19-Impact on Quality of Life(COV19-QoL)scale Arabic version,after assessing Content validity and ***:The total QoL score(mean±standard deviation)is 2.3±0.6 and the score for QoL in general and perception of danger on personal safety show the highest mean with 2.6±*** lowest mean score is related to the perception of mental health deterioration(1.9±0.8).Independent predictors of the total QoL scale are sex(regression coefficient(95%CI)=0.1(0.02 to 0.2),p value=0.02),monthly income(regression coefficient(95%CI)=0.1(0.004 to 0.2),p value=0.04),knowing someone infected with COVID-19(regression coefficient(95%CI)=0.15(0.08 to 0.3),p value=0.001),and data collection time(regression coefficient(95%CI)=0.1(0.006 to 0.2),p value=0.04).Conclusions:COVID-19 pandemic has impacted the public quality of life,particularly in terms of general quality of life and personal *** with substantial predictors of lower quality of life should be given more attention.

关键词： COVID-19 Quality of life mental health Community-based participatory research

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Neutron and Ion Beams Emitted from Plasma Focus (112.5 J) Device

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Plasma Science and Technology 2010年第1期12卷 1-5页

作者： G.m.el-ARAGI Plasma Physics and Nuclear Fusion Department Nuclear Research Center

Preliminary results of recent experiments performed within the mather-type 112.5 J plasma focus device are presented. The ion beams from the focus device operated with deuterium filling at 1 mbar were registered using CR-39 solid state nuclear track detectors （SSNTD） and a Faraday cup detector for time-resolved measurements. The time-resolved neutron emission from the focus region measurements was detected with a photomultiplier tube （IP-28） optically coupled with a plastic scintillator NE 102.

关键词： plasmas neutron scintillator detectors photomultiplier Faraday

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Research in Astronomy and Astrophysics 2010年第12期10卷 1275-1286页

作者： mohsen Nejad-Asghar Department of Physics University of Mazandaran Research Institute for Astronomy and Astrophysics of maragha Department of Physics Damghan University

Theoretically, stars formed from the collapse of cores in molecular clouds. Historically, the core had been assumed to be a singular isothermal sphere （SIS）, and the collapse had been investigated in a self-similar manner. When the rotation and magnetic fields lead to non-symmetric collapse, a spheroidal shape may occur. Here, the result of the centrifugal force and magnetic field gradient is assumed to be in the normal direction to the rotational axis, and its components are supposed to be a fraction β of the local gravitational force. In this research, a collapsing SIS core is considered to find the importance that the parameter β plays in the oblateness of the mass shells, which are the crests of the expansion waves. We apply the Adomian decomposition method to solve the system of nonlinear partial differential equations because the collapse does not occur in a spherically symmetric and self-similar man- ner. In this way, we obtain a semi-analytical relation for the mass infall rate m of the shells in the envelope. Near the rotational axis, m˙ decreases with the increase of the non-dimensional radius ξ, while a direct relation is observed between m˙ and ξ in the equatorial regions. Also, the values of m˙ in the polar regions are greater than their equatorial values, and this difference occurs more often at smaller values of ξ. Overall, the results show that before reaching the crest of the expansion wave, the visible shape of the molecular cloud cores can evolve into oblate spheroids. The ratio of major to minor axes of oblate cores increases when increasing the parameter β, and its value can approach the observed elongated shapes of cores in the maps of molecular clouds, such as those in Taurus and Perseus.

关键词： ISm: clouds -- ISm: evolution -- stars: formation - methods: analytical

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Parasites of the Nile rat in rural and urban regions of Sudan

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Integrative Zoology 2009年第2期4卷 179-187页

作者： Dina m.FAGIR el-Amin el-RAYAH Department of Zoology University of KhartoumKhartoumSudan

In this investigation on endoparasites(helminths)and ectoparasites of the Nile rat(Arvicanthis niloticus Desmarest,1822),a total of 220 Nile rats were trapped from different regions of Sudan during the period January 2003–January *** of different tissues,identification of parasites,effect of these parasites on the organs,the preva-lence and intensity of infestation of the parasites and their relation to the habitat of the host,and sex-related infestations were *** showed that the variation among helminth species was wide,especially in those that are transferred by *** protozoan parasites or distortion in the infected tissues were *** examination for Toxoplasma gondii was carried *** species of cestodes(Hymenolepis nana,Hymenolepis diminuta),two genera(Raillietina sp.I,Raillietina ***)and one unidentified Hymenolepididae were *** most prevalent species of cestodes was Raillietina *** for nematodes only one species and one genus were recovered(monanema nilotica and Streptopharagus sp.).Investigation of skin revealed that 83.8%of rats were infested with one or more of ectoparasites;namely,insects and *** survey also revealed that fleas and lice were the most common ectoparasites that infested the Nile *** rodents,particularly those living in close association with man,play a significant role in human health,welfare and *** has to be stressed that their arthropod ectoparasites are important vectors of pathogenic microorganisms and they can also be important reservoirs for parasitic zoonoses,like trichinellosis and *** doubt,the increase in rodent populations could be followed by an increase in zoonotic diseases(Stojcevic et al.2004,Durden et al.2000).Rats and mice(commensal and wild)play an important role in public health,being carriers or reservoirs for infectious diseases that can be transmitted to humans(zoonoses).Xenopsylla cheopis is the most important vector

关键词： Arvicanthis fleas lice mites Nile rat Sudan ticks.

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