小麦粒重杂种优势的表现

通过3轮机械混选,从UP363×WC457、UP368×Shailza和WH157×Bulk 1858 3个杂交组合的后代群体中选育出5个具有不同粒重的品系。这些品系以及Sonalika品种之间进行除反交外的各种可能的杂交。粒重最重(65g)的品系几乎与最重的杂种相当。不同相联度亲本的杂种是等于还是低于中值取决于相联度,并因此表现出负的杂种优势或者无杂种优势。含有等位基因离散亲本的杂种粒重高,且具有高的正杂种优势。因此,等位基因的离散是杂种优势的主要原因。配合力效应受亲本中等位基因分布方式的影响。相联亲本表现出正的一般配合力(gca)效应,而离散亲本则表现出负的一般配合力效应。

Biosorption of Ni(Ⅱ) ions from aqueous solution using modified Aloe barbadensis Miller leaf powder

This study aimed to investigate the biosorption potential of Na2CO3-modified Aloe barbadensis Miller (Aloe vera) leaf (MABL) powder for removal of Ni(II) ions from a synthetic aqueous solution. Effects of various process parameters (pH, equilibrium time, and temperature) were investigated in order to optimize the biosorptive removal. The maximum biosorption capacity of MABL was observed to be 28.986 mg/g at a temperature of 303 K, a biosorbent dose of 0.6 g, a contact time of 90 min, and a pH value of 7. Different kinetic models (the pseudo-first-order, pseudo-second-order, Elovich, and intraparticle diffusion models) were evaluated. The pseudo-second-order kinetic model was found to be the best fitted model in this study, with a coefficient of determination of R^2 =0.974. Five different isotherm models (the Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, and Brunauer-Emmett-Teller (BET) models) were investigated to identify the best-suited isotherm model for the present system. Based on the minimum chi-square value (X^2 =0.027) and the maximum coefficient of determination (R^2 =0.996), the Langmuir isotherm model was found to represent the system well, indicating the possibility of monolayer biosorption. The sticking probability (S*) was found to be 0.41, suggesting a physisorption mechanism for biosorption of Ni(II) on MABL. The biosorbent was characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), zeta potential, and BET surface area, in order to understand its morphological and functional characteristics.

Magnetizations and magneto-transport properties of Ni-doped PrFeO_3 thin films

The present study reports the magnetizations and magneto-transport properties of PrFel_xNixO3 thin films grown by pulsed laser ablation technique on LaA103 snbstrates. From DC M/H plots of these films, weak ferromagnetism or ferrimagnetism behaviors are observed. With Ni substitution, reduction in saturation magnetization is also seen. With Ni doping, variations in saturation field （Hs）, coercive field （Hc）, Weiss temperature （0）, and effective magnetic moment （Pelf） are seen. A small change of magnetoresitance with application of higher field is observed. Various essential parameters like density of state （Nf） at Fermi level, Mott＇s characteristic temperature （To）, and activation energy （Ea） in the presence of and in the absence of magnetic field are calculated. The present observed magnetic properties are related to the change of Fe-O bond length （causing an overlap between the oxygen p orbital and iron d orbital） and the deviation of the Fe-O-Fe angle from 180~. Reduction of magnetic domain after Ni doping is also explored to explain the present observed magnetic behavior of the system. The influence of doping on various transport properties in these thin films indicates a distortion in the lattice structure and single particle band width, owing to stress-induced reduction in unit cell volume.

Influence of Crop Nutrition on Grain Yield,Seed Quality and Water Productivity under Two Rice Cultivation Systems

The system of rice intensification （SRI） is reported to have advantages like lower seed requirement,less pest attack,shorter crop duration,higher water use efficiency and the ability to withstand higher degree of moisture stress than traditional method of rice cultivation.With this background,SRI was compared with traditional transplanting technique at Indian Agricultural Research Institute,New Delhi,India during two wet seasons （2009-2011）.In the experiment laid out in a factorial randomized block design,two methods of rice cultivation [conventional transplanting （CT） and SRI] and two rice varieties （Pusa Basmati 1 and Pusa 44） were used under seven crop nutrition treatments,viz.T 1,120 kg/hm2 N,26.2 kg/hm2 P and 33 kg/hm2 K;T 2,20 t/hm2 farmyard manure （FYM）;T 3,10 t/hm2 FYM＋ 60 kg/hm2 N;T 4,5 t/hm2 FYM＋ 90 kg/hm2 N;T 5,5 t/hm2 FYM＋ 60 kg/hm2 N＋ 1.5 kg/hm2 blue green algae （BGA）;T 6,5 t/hm2 FYM＋ 60 kg/hm2 N＋ 1.0 t/hm2 Azolla,and T 7,N 0 P 0 K 0 （control,no NPK application） to study the effect on seed quality,yield and water use.In SRI,soil was kept at saturated moisture condition throughout vegetative phase and thin layer of water （2-3 cm） was maintained during the reproductive phase of rice,however,in CT,standing water was maintained in crop growing season.Results revealed that CT and SRI gave statistically at par grain yield but straw yield was significantly higher in CT as compared to SRI.Seed quality was superior in SRI as compared to CT.Integrated nutrient management （INM） resulted in higher plant height with longer leaves than chemical fertilizer alone in both the rice varieties.Grain yield attributes such as number of effective tillers per hill,panicle length and panicle weight of rice in both the varieties were significantly higher in INM as compared to chemical fertilizer alone.Grain yields of both the varieties were the highest in INM followed by the recommended doses of chemical fertilizer.The grain yield and its attributes of Pusa 44 were significantly higher than those of Pusa Basmati 1.The seed quality parameters like germination rate and vigor index as well as N uptake and soil organic carbon content were higher in INM than those in chemical fertilizer alone.CT rice used higher amount of water than SRI,with water saving of 37.6% to 34.5% in SRI.Significantly higher water productivity was recorded in SRI as compared to CT rice.

计算机配色

纱线中纤维的转移既是必要的,又是有害的。因为没有纤维的转移,就不可能有一个连接良好的纱线结构,而且纱线也将不能承受任何张力。因此对一根纺出的纱而言,纤维的转移是必要的。至于说有害,是因为基于纱线的结构,纤维的转移会使对纱线力学性能的理论论述变得困难。不同的工作者提出了众多的纤维转移测量方法。Hearl、Gupta和Merhant已明确了纱线中纤维的理想转移,在这种理想转移中,纤维规则而整齐地从纱线外层向纱芯转移,随之又回到外层,这种方式下纱线中纤维集合体的密度保持为常数。

CaMoO_4:Dy^(3+),K^+ near White Light Emitting Phosphor:Structural,Optical and Dielectric Properties

Undoped, Dy^3＋ doped and Dy^3＋, K^＋ codoped calcium molybdate phosphors have been synthesized by solid-state reaction method. X-ray diffraction studies reveal the tetragonal structure of the prepared phosphors having crystallite size 15-50 nm. Scanning electron microscopy （SEM） studies reveal the morphology and crystallite size of the prepared phosphors. Photoluminescence studies indicate that there are blue and yellow emissions at 489 and 576 nm, respectively corresponding to Dy^3＋ ion. The introduction of K＋ ion significantly influences the blue and yellow emissions which causes the near white light emission from this codoped phosphor. The intense absorption peak of the codoped phosphor at 210 nm is attributed to the band gap and a shoulder at 240 nm appears due to charge transfer from oxygen ions to neighbouring molybdenum ions. The band gap of the codoped phosphor is calculated as 5.5 eV from the absorption studies. The dielectric properties such as permittivity and dielectric loss are studied as a function of frequency.Acknowledgement The authors are thankful to the Department of Science and Technology, New Delhi （Government of India） for funding this work under the Project SR/FTP/PS-087/2010.

Seasonal variability of ambient NH_3, NO, NO_2 and SO_2 over Delhi

We present the diurnal and seasonal variability of ambient NH3, NO, NO2 and SO2 over Delhi, India. Ambient NH3, NO and NO2 were measured continuously during winter, summer and autumn seasons using NH3- and NOx-analyzer, which operates by chemiluminescence method with a higher estimation efficiency （〉 90%） than the chemical trap method （reproducibility 4.7%）. Prominent diurnal, day-to-day and seasonal variations of ambient mixing ratio of NH3, NO, NO2 and SO2 were observed during the study period. Seasonal variation with higher mixing ratio in winter was observed for all measured trace gases except NO. Day-night variation of all measured trace gases observed was higher in winter in comparison with summer. Late morning increase in NO2 mixing ratio might be attributed to conversion of NO to NO2 with the interaction ofO3.

Effect of Substrate and Annealing Temperatures on Mechanical Properties of Ti-rich NiTi Films

The effect of substrate and annealing temperatures on mechanical properties of Ti-rich NiTi films deposited on Si （100） substrates by DC magnetron sputtering was studied by nanoindentation.NiTi films were deposited at two substrate temperatures viz.300 and 400 ℃.NiTi films deposited at 300 ℃ were annealed for 4 h at four different temperatures,i.e.300,400,500 and 600 C whereas films deposited at 400 ℃ were annealed for 4 h at three different temperatures,i.e.400,500 and 600 ℃.The elastic modulus and hardness of the films were found to be the same in the as-deposited as well as annealed conditions for both substrate temperatures.For a given substrate temperature,the hardness and elastic modulus were found to remain unchanged as long as the films were amorphous.However,both elastic modulus and hardness showed an increase with increasing annealing temperature as the films become crystalline.The results were explained on the basis of the change in microstructure of the film with change in annealing temperature.