Investigation of summer monsoon rainfall variability in Pakistan     

Mian Sabir Hussain  Seungho Lee 《Meteorology and Atmospheric Physics》2016,128(4):465-475

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Distribution of heavy metals in Port Phillip Bay     

V. Talbot  R.J. Magee  M. Hussain 《Marine pollution bulletin》1976,7(3):53-55

The distribution of cadmium, copper, iron, manganese, lead, and zinc in sediments of Port Phillip Bay, Victoria, Australia was investigated, and the impact of industrial discharges studied. The pre-cultural levels for these metals are in nearly all cases far less than the post-cultural levels, especially in those sediments deposited in the last half century in the vicinity of urbanized areas.  相似文献   

Weather yield model for the semi tropical region (Pakistan)     

Syed Faizan Haider  K. H. Asif  Amjad Hussain Gilani 《大气科学进展》1992,9(3):367-372

Weather models are essential tools for checking of the effect of the weather elements in terms of their effect on the production of the crop. This research is an attempt to see the effect of only two variables i.e., temperature and rainfall for the division Faisalabad (semitropical region of Pakistan).The model fitted is of the linear form:the values of a,b, c have been found. The expected yield has been calculated by using the aridity indices (X1 and X2 ) and the result in the form of coefficient of determination R2 has been found equal to 0.166. The significance of the regression coefficient has been tested, which shows that the contribution to the yield from aridity index at germination and that at ripening is significant.The wheat yields are the results of a wide variety of variables, most of which show varying degree of relationship with one another, some positive and some negative in terms of output. These variables may be technology, fertilizers, pesticides, epidemics, kinds of seeds used, market price of crop and the area under cultivation etc, which can be the source of variation in the wheat yield. Since rainfall during germination and temperature at the ripening periods are the necessary factors for the yield of wheat, for this purpose these parameters have been studied in order to their contribution.  相似文献   

U-238 series radioactive disequilibrium in groundwaters: implications to the origin of excess U-234 and fate of reactive pollutants     

N. Hussain  S. Krishnaswami 《Geochimica et cosmochimica acta》1980,44(9):1287-1291

The concentrations of ²³⁸U, ²³⁴Th, ²²⁶Ra, ²²²Rn and ²¹⁰Pb and ${}^{234}\text{U}{}^{238}\text{U}$ activity ratios have been measured in several groundwater samples from Gujarat, India. In the aqueous phase the abundances of ²³⁴Th and ²¹⁰Pb are grossly deficient relative to their parents, ²³⁸U and ²²²Rn respectively. The deficiency is ascribable to the impact adsorption of ²³⁴Th and ²¹⁰Pb atoms onto particle surfaces which are very abundant in the groundwater regimes. The scavenging residence times for both these nuclides is about a day, suggesting that irreversible removal of ‘reactive’ metals and pollutants in groundwaters can occur on very short time scales. The fast removal of ²³⁴Th onto particles necessitates that in these groundwaters ²³⁴U ‘excess’ has to originate through leaching of soil grains rather than through in situ decay of dissolved ²³⁴Th in the water.  相似文献   

Relation between trace and major element composition of the Chitaldrug metabasalts,Mysore, India,and the Archaean mantle     

S.M. Naqvi  S.M. Hussain 《Chemical Geology》1973,11(1):17-30

The ferromagnesium trace-element content of the Chitaldrug metabasalts is not compatable with its normative composition. The major elements resemble quartz-normative tholeiites and some trace-elements like Co are even higher or similar to that of olivine-normative tholeiites or the deep-oceanic tholeiites. The relationship between MgO and ferromagnesium traces is sympathetic but of very low order. The high ferromagnesium trace content in this suite and its poor relation with major elements suggest that probably the Archaean/Early Precambrian upper mantle had higher levels of these elements than the present mantle. Lateral compositional inhomogeneities in the Archaean upper mantle are also indicated from the available trace-element data over the Archaean metabasalts from different shields.  相似文献   

A continuous time delay-difference type model (CTDDM) applied to stock assessment of the southern Atlantic albacore <Emphasis Type="Italic">Thunnus alalunga</Emphasis>     

廖宝超  刘群  张魁  韩亚楠 《中国海洋湖沼学报》2016,34(5):977-984

A continuous time delay-diff erence model (CTDDM) has been established that considers continuous time delays of biological processes. The southern Atlantic albacore (Thunnus alalunga) stock is the one of the commercially important tuna population in the marine world. The age structured production model (ASPM) and the surplus production model (SPM) have already been used to assess the albacore stock. However, the ASPM requires detailed biological information and the SPM lacks the biological realism. In this study, we focus on applying a CTDDM to the southern Atlantic albacore (T. alalunga) species, which provides an alternative method to assess this fishery. It is the first time that CTDDM has been provided for assessing the Atlantic albacore (T. alalunga) fishery. CTDDM obtained the 80% confidence interval of MSY (maximum sustainable yield) of (21 510 t, 23 118t). The catch in 2011 (24 100 t) is higher than the MSY values and the relative fishing mortality ratio (F ₂₀₁₁/F _MSY) is higher than 1.0. The results of CTDDM were analyzed to verify the proposed methodology and provide reference information for the sustainable management of the southern Atlantic albacore stock. The CTDDM treats the recruitment, the growth, and the mortality rates as all varying continuously over time and fills gaps between ASPM and SPM in this stock assessment.  相似文献   

Age and isotopic constraints on magmatism along the Karakoram-Kohistan Suture Zone,NW Pakistan: evidence for subduction and continued convergence after India-Asia collision   总被引：1，自引：0，他引：1  

Stefan Heuberger  Urs Schaltegger  Jean-Pierre Burg  Igor Maria Villa  Martin Frank  Hamid Dawood  Shahid Hussain  Andrea Zanchi 《Swiss Journal of Geoscience》2007,100(1):85-107

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Temperature dependence of photoluminescence emission characteristics in a natural fluorite     

F. O. Ogundare  F. A. Balogun  L. A. Hussain 《Mineralogy and Petrology》2007,90(3-4):167-173

Summary The temperature dependence of photoluminescence emission of a natural fluorite has been studied in the wavelength region of 380–500 nm and in the temperature range of 17.5–300 K. The emission spectra of the sample show a broad emission band between 380 and 500 nm for temperatures above 100 K. At 100 K and below, vibronic lines appear on the emission band at approximately 413.3, 418.1, 419.3, 420.2, 423.9 and 427.1 nm. This broad emission band and the vibronic lines in fluorite are usually associated with phonon-coupled electronic transitions from 4f⁶5d to 4f⁷ in the Eu²⁺ ion. Temperature dependences of the peak energy, intensity and full-width at half-maximum of the broad emission band are discussed, and the behaviour explained in terms of a configurational coordinate model. The excited state vibrational energy was obtained to be 0.023 ± 0.001 eV and this is lower than the LO phonon energy of 0.062 eV in pure fluorite. The activation energy of thermal quenching of the photoluminescence intensity was found to be 0.022 ± 0.002 eV.  相似文献   

Genotype and environmental interaction in cowpea (Vigna Unguiculata-L) for yield and disease resistance     

Y. Ali  Z. Aslam  F. Hussain  A. Shakur 《International Journal of Environmental Science and Technology》2004,1(2):119-123

Twenty-six cowpea cultivars were tested for yellow mosaic virus resistance at NIAB Faisalabad. NCPM-1, Elite, IT-84-552, No.44, P-518, S.A. Dandy, IT-97k-350-4, IT-93K-452, IT-97K-1042-8 and IT-97K-497-2 showed resistant reaction to yellow mosaic virus disease. As the study was aimed to select disease resistant and high yielding cultivars. Five cultivars viz. NCPM-1, Elite. S.A. Dandy, IT-97K-497-2 and IT-97K-1042-8 were chosen and evaluated at five different ecological zones during the year 2003. At each location, the experiment was laid out in a randomized complete block design keeping 7.2 m² plot size in three repeats. At maturity the seed yield was collected and subjected to analysis of variance following stability parameters, varieties, environment and varieties x environment showed significant differences. Significant and highest seed yield (880 kg/ha) was observed in NIAB cowpea mutant-1 followed by Elite (729 Kg/ha). The highest yielding genotypes i.e. NIAB cowpea Mutant-1 and Elite showed non-significant differences of regression coefficient from one. Moreover these genotypes also exhibited non-significant difference of standard deviation to regression from zero. Based on three parameters i.e. high mean seed yield, regression coefficient and standard deviation to regression, these genotypes showed excellent and trustworthy stable performance over different environment. Hopefully these genotypes will definitely be helpful for increasing one local production of cowpea crop.  相似文献   

Petrological and Geochemical Characteristics of Archean Gneisses and Granitoids from Bastar Craton, Central India – Implication for Subduction Related Magmatism     

M.F. Hussain  M.E.A. Mondal  T. Ahmad   《Gondwana Research》2004,7(2):531-537

The gneisses and granitoids of Bastar craton (with rock suites up to 3.5 Ga) show calc-alkaline trondhjemitic characteristics. The rocks are enriched in both LILE and HFSE than primordial mantle. They have also relatively higher abundances of LILE and strong depletion at P and Ti in the multielement diagram. The depletion of Ti and P indicates retention of these elements by titanite and/or apatite during partial melting. It is proposed that subduction of an oceanic slab and its consequent melting led to the formation of the protoliths of the gneisses without much interaction with the mantle wedge. The granitoids represent temporally distinct suites formed in response to further melting of slab at greater depth and interaction of magma with the mantle wedge during their transport to the crust.  相似文献