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| 1 | Enhanced photocatalytic activity of Ce-doped ZnO nanopowders synthesized by combustion method显示文摘Facile and fast combustion method was used to synthesize Zn O and Ce-doped Zn O(CZO) nanocrystalline powders photocatalysts with different cerium concentrations(0.5 wt.%–10.0 wt.%) followed by calcination at 700 oC for 3 h. The prepared samples were characterized by a variety of characterization techniques such as X-ray diffraction(XRD), scanning electron microscopy(SEM) combined with energy dispersive X-ray diffraction(EDX), transmission electron microscopy(TEM), UV-visible spectroscopy, BET surface area analyser and photoluminescence spectroscopy(PL), to study the crystal structure, surface morphology, chemical composition and optical properties. It was observed from XRD results that synthesized powders had hexagonal wurtzite structure with the smallest crystallite size about 13 nm. Absorption spectra showed that cerium doping enhanced the light absorption properties towards the visible light region. Photoluminescence spectra for Ce-doped Zn O samples exhibited relatively weak near band edge(NBE) emission peaks as compared to that of pristine Zn O. The photocatalytic activities of the prepared samples were evaluated by photocatalytic degradation of Rhodamine B(Rh B) under UV light and visible light(λ≥420 nm) irradiation. The textile mill effluent containing organic matters was also treated under sunlight using photocatalysis and the reduction in the chemical oxygen demand(COD) of the treated effluent revealed a complete destruction of the organic molecules along with colour removal. The results showed that the CZO photocatalyst doped with 3.0 wt.% cerium exhibited four times enhanced photocatalytic activity compared to pure Zn O. The enhanced photocatalytic activity could be attributed to extended visible light absorption and inhibition of the electron-hole pair's recombination. | M.Ahmad E.Ahmed Fezza Zafar N.R.Khalid N.A.Niaz Abdul Hafeez M.Ikram M.Ajmal Khan 洪樟连 | 2015 | Journal of Rare Earths2015，33，3： | 13 |
| 2 | Ageing Effect on Hardness and Microstructure of Al-Zn-Mg Alloys显示文摘Experimental results of the investigation on the hardness of two Al-Zn-Mg alloys [Al-10.0 Zn- 4.0 Mg and Al-8.5 Zn-3.0 Mg (wt pct)] aged in the temperature range 60-310℃ for different intervals of time from 1/4 h to 168 h are presented. Both the alloys were found to show identical behaviour of hardness with ageing time. Alloy with higher Zn and Mg content had higher hardness than the alloy with lower solute content. There were three ranges of temperature in which different types of precipitates formed and affected the hardness. Some of the grain boundaries were found to migrate and precipitate free zone has been observed. | M.Iqbal, M.A.Shaikh, M.Ahmad and K.A.Shoaib (Nuclear Physics Division, Pakistan Institute of Nuclear Science and Technology P.O.Nilore, Islamabad, Pakistan) | 2000 | Journal of Materials Science & Technology2000，16，3： | 5 |
| 3 | Fermentation, formulation and evaluation of PGPR Bacillus subtilis isolate as a bioagent for reducing occurrence of peanut soil-borne diseases显示文摘Four isolates of Bacillus subtilis coded,B4,B7,B8 and B10 were examined as biocontrol agents for their abilities and antagonistic effect on the in vitro growth of certain phytopathogenic fungi of peanut,Rhizoctonia solani and Sclerotium rolfsii.Bacillus subtilis isolate B4(GenBank accession no.EF150884)was the highly effective one for inhibiting the fungal mycelial growth.Batch fermentation of B.subtilis isolate B4 was carried out and the maximum biomass achieved was 4.53 g L-1 at 11 h.Bacillus subtilis isolate B4 was formulated and evaluated as a biofungicide to reduce peanut soil-borne diseases under greenhouse and field conditions at the side of Rizolex-T(fungicide)as standard.Treatments by formulated plant growth-promoting rhizobacteria(PGPR)B.subtilis B4 and Rizolex-T in a soil infested with R.solani,S.rolfsii and mixture of them were more effective in decreasing percentage of damping-off,root and pod rot disease incidence(%)in greenhouse and open field environment during the two seasons 2015 and 2016.Treatments by PGPR gave highly dry weight and number of healthy pods compared to control of fungi treatment which was nearby to dry weights of healthy pods achieved by treatments by Rizolex-T in a soil infested with S.rolfsii,R.solani and mixture of them.Formulated PGPR B.subtilis B4 gave higher increasing of yield percentage than treatment by Rizolex-T in the two evaluated seasons 2015 and 2016.It can conclude that the produced bioforumlated agent was more efficient as fungicide when compared with the other chemical synthesized fungicides,safe for human and the environment and economy. | Abdel-Gayed M.Ahmad Abo-Zaid G.Attia Matar S.Mohamed Hafez E.Elsayed | 2019 | Journal of Integrative Agriculture2019，18，9： | 3 |
| 4 | Hepatitis C virus‐core and non structural proteins lead to different effects on cellular antioxidant defenses显示文摘 | Maher Y.Abdalla Iman M.Ahmad Douglas R.Spitz Warren N.Schmidt Bradley E.Britigan | 2005 | J Med Virol2005，，4： | 1 |
| 5 | More than a simple egg:Underlying mechanisms of cold tolerance in avian embryos显示文摘Avian embryos,which develop within eggs,exhibit remarkable tolerance to extremely low temperatures.Despite being a common trait among all birds,the mechanisms underlying this cold tolerance in avian embryos remain largely unknown.To gain a better understanding of this phenomenon and the coping mechanisms involved,we reviewed the literature on severe cold tolerance in embryos of both wild and domestic birds.We found that embryos of different bird orders exhibit tolerance to severe cold during their development.In response to cold stress,embryos slow down their heartbeat rates and metabolism.In severe cold temperatures,embryos can suspend these processes,entering a torpid-like state of cardiac arrest.To compensate for these developmental delays,embryos extend their regular incubation periods.Depending on their embryonic age,embryos of all bird species can tolerate acute severe cold regimes;only a few tolerate chronic severe cold regimes.We also discussed various extrinsic and intrinsic factors that affect the tolerance of bird embryos to low temperatures before and after incubation.Cold tolerance appears to be a heritable trait shared by wild and domestic embryos of all bird classes,regardless of egg size or development(altricial/precocial).Driven by environmental variability,cold tolerance in avian embryos is an optimal physiological and ecological strategy to mitigate the adverse effects of cold conditions on their development in response to fluctuating environmental temperatures. | Ibrahim M.Ahmad Dongming Li | 2023 | Avian Research2023，14，2： | 1 |
| 6 | Seasonal variations in gonad morphology and hypothalamic GnRH-I and GnIH in Eurasian Tree Sparrow,a multi-brooded passerine显示文摘The hypothalamic-pituitary-gonadal(HPG)axis ubiquitously regulates seasonal reproduction,following the rhythmicity of a suite of environmental cues.Birds display prominent seasonal variations in gonad size regulated by two hypothalamic peptides,gonadotropin-releasing hormone-1(GnRH-I)and gonadotropin-inhibiting hormone(GnIH).How multi-brooded avian species adjust GnRH-I and GnIH to regulate gonadal morphology seasonally remains largely unknown.Here,we studied the variations in the hypothalamic immunoreactivity(ir)of GnRH-I and GnIH,gonadal proliferation,and apoptosis in a typical multi-brooded species,the Eurasian Tree Sparrow(Passer montanus),across the pre-breeding(PB),first breeding(FB),second breeding(SB),pre-basic molt(PM),and wintering stages(WS).Our results showed that both sexes had higher preoptic area(POA)-GnRH-I-ir but lower paraventricular nucleus(PVN)-GnIH-ir neurons during the breeding stages(FB and SB)relative to other life-history stages,with no significant differences between two broods.The testes and ovaries were significantly larger during the breeding stages.Testicular volume increased during the two broods due to anincreased diameter of seminiferous tubules.Furthermore,there were more testicular apoptotic cells in PB and WS stages than in breeding stages,and in PB stage than in PM stage.Males had higher POA-GnRH-I expression than females during the breeding stages,but both sexes had comparable PVN-GnIH expression throughout the annual cycle.Both sexes of the sparrows may undergo a similar pattern of life-history stage-dependent variation in the hypothalamic GnRH-I,GnIH,and gonadal morphology,except that during breeding stages,males may display higher expression of POA-GnRH-I relative to females.The higher expression of POA-GnRH-I-ir in breeding male sparrows may be critical for male-dependent parental care. | Limin Wang Ghulam Nabi Li Zhang Dan Liu Mo Li Juyong Li Kaixin Shi Ibrahim M.Ahmad Yuefeng Wu John C.Wingfield Dongming Li | 2022 | Avian Research2022，13，3： | 0 |
| 7 | Particle Size Distribution and Characterization of High Siliceous and Microporous Materials显示文摘Particle size, textural and surface characteristics influence some major technological properties of high siliceous aluminosilicate zeolite and sillicoaluminophosphate (SAPO) microporous materials. A comparative study was furnished for measuring surface characteristics, particle size and particle size distribution using particle size analyzer (PSA)and scanning electron microscope (SEM). The PSA is capable of measuring particle diameter in micron range. The results of these techniques for estimation of particle size were compared and correlated statistically. Student t-test and variance ratio test (F-test) methods were performed for the significance of results by the analysis of variance (ANONA) and multiple-range tests. Textural and surface characteristics were evaluated by Brunauer, Emmett &Teller (BET) volumetric technique and v-αs plotting method. The textural results shows that the external surface area and micropore volume of microporous materials were higher than those of the high siliceous zeolites and its zeotype materials. | S.KDurrani J.Akhtar M.Ahmad M.J.Moughal | 2005 | Journal of Materials Science & Technology2005，21，4： | 0 |
| 8 | Hibernation with rhythmicity:the circadian clock and hormonal adaptations of the hibernating Asiatic toads(Bufo gargarizans)显示文摘Hibernation is one of the fundamental strategies in response to cold environmental temperatures.During hibernation,the endocrine and circadian systems ensure minimal expenditure of energy for survival.The circadian rhythms of key hormones,melatonin(MT),corticosterone(CORT),triiodothyronine(T3),and thyroxine(T4),and the underlying molecular regulatory mechanisms of hibernation have been well determined in mammals but not in ectotherms.Here,a terrestrial hibernating species,Asiatic toad(Bufo gargarizans),was employed to investigate the plasma CORT,MT,T3,and T4;and the retina,brain,and liver mRNA expression of the core clock genes,including circadian locomotor output cycles kaput(Clock),brain and muscle ARNT-like 1(Bmal1),cryptochrome(Cry)1 and 2,and period(Per)1 and 2,at 7-time points over a 24-h period under acute cold(1 day at 4℃),and hibernation(45 days at 4℃).Our results showed that the circadian rhythms of the core clock genes were rather unaffected by acute cold exposure in the retina,unlike the brain and liver.In contrast,during hibernation,the liver clock genes displayed significant circadian oscillations,while those in the retina and brain stopped ticking.Furthermore,plasma CORT expressed circadian oscillations in both groups,and T3 in acute cold exposure group,whereas T4 and MT did not.Our results reveal that the plasma CORT and the liver sustain rhythmicity when the brain was not,indicating that the liver clock along with the adrenal clock synergistically maintains the metabolic requirements to ensure basic survival in hibernating Asiatic toads. | Zhigang XIE Ibrahim M.AHMAD Lirong ZUO Feng XIAO Yongpeng WANG Dongming LI | 2022 | Integrative Zoology2022，17，4： | 0 |
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