The Lone Pair Electrons in Post-Transition Metal and Their Contribution to Optical Response

The stereochemically active lone pairs around post-transition metal atoms play an important role in determining distorted lattice structure and optical response.The lone pair electrons are characterized by crystal orbitals,electron localization function(ELF)and partial density of states(PDOS).Birefringence is evaluated by means of a Born effective charge approach based on modern polarization theory.The origin of the different responses of birefringence and second-harmonic generation(SHG)is explored,as well as the effect of spin-orbit coupling(SOC)on the band structure and optical properties is explored.The study of this paper can help to deeply understand the lone pairs and their contribution to optical property.

Temporal-spatial Changes in Inner Mongolian Grassland Degradation during Past Three Decades

[Objective] This study aimed to analyze the temporal-spatial variation of Inner Mongolian grassland degradation during past three decades. [Method] The dis- tribution characteristics of grassland were described by land use types supervised classification with TM/ETM. Then, temporal-spatial changes of grassland coverage were quantified by the mean of maximum vegetation coverage in last 30 years. Lastly, the grassland degradation reasons were explored through statistic analysis between the grassland coverage and precipitation, temperature and grazing intensity. [Result] The grassland degradation index of Inner Mongolia was increased from 1.38 to 1.68, and the smallest was 1.28 in 2005s. Grassland degradation and improve- ment were concurrent after 1980s, but grassland degradation was the major change trend for Inner Mongolia grassland. The area of grassland degradation was enlarged from 18.08×10^4 km2 in 1980s to 22.47×10^4 km2 in 2010s on the whole and distribu- tion range was shifted from central-eastern to west in Inner Mongolia that mainly distributed on Hulun Buir and Xilin Gol grassland in 1980s and Ordos and Alax grassland in 2010s. The grassland area of degradation had a rising trend form 1980s to 1995s, then reduced to 10.8x104 km2 in 2005s, and decreased in 2010s, which mainly speared in the west of Xilin Gol grassland. [Conclusion] Inner Mongo-lian grassland degradation were become more seriously in last 30 years because that temperature, precipitation and graze intensities change, which not performance on decreasing coverage but grassland areas.

Correlation Analysis between Fruit Cracking and Influencing Factors in Apricot

In this study, 14 representative apricot cultivars in the production were selected as the experimental materials, and their fruit cracking characteristics, as well as the correlations between fruit cracking and influencing factors （e.g., pedcarp structure, mineral elements contents, DW/FW ratio and soluble sugar content） were analyzed to provide some reference for systematic study on fruit cracking mecha- nism of apricot. The results showed the cultivars with small orderly-and compactlyarranged epidermal cells were difficult to crack, while the cultivars with big disorderly-and loosely-arranged epidermal cells were easy to crack. There was no significant correlation between pericarp thickness and cracking index. The correlations between cracking and mineral elements contents of apricot fruit were in the order as Ca 〉 Zn 〉 Mn 〉 Fe 〉 K 〉 Mg 〉 Cu. The cracking index of apricot fruit was significantly negatively correlated with Ca content, was weakly correlated with Zn and Mn contents, and was uncorrelated with Fe, K, Mg and Cu contents. Ca deficiency was the main factor affecting the fruit cracking in apricot. Under the same conditions, the higher the water content is, the lower the cracking index is; and the higher the soluble sugar content is, the higher the cracking index is.

Research Progress on Methane Emission from Cropland

Methane is an important greenhouse gas, and farmland is one of the im- portant emission sources of methane. Therefore, it＇s important to study the discharge of methane from cropland. This paper reviewed the methane emission from agricultural ecosystem, the factors controlling CH4 fluxes from soil, such as water regime, the soil characteristics, and the type and amount of applied fertilizers and so on, the management for mitigation of CH4 emission from cropland, especially from paddy field, and put forward some research suggestions on methane emission in the future. The objective of this paper is to provide reference for controlling methane emission in cropland.

Dynamics models of soil organic carbon

As the largest pool of terrestrial organic carbon, soils interact strongly with atmosphere composition, climate, and land change. Soil organic carbon dynamics in ecosystem plays a great role in global carbon cycle and global change. With development of mathematical models that simulate changes in soil organic carbon, there have been considerable advances in understanding soil organic carbon dynamics. This paper mainly reviewed the composition of soil organic matter and its influenced factors, and recommended some soil organic matter models worldwide. Based on the analyses of the developed results at home and abroad, it is suggested that future soil organic matter models should be developed toward based-process models, and not always empirical ones. The models are able to reveal their interaction between soil carbon systems, climate and land cover by technique and methods of GIS (Geographical Information System) and RS (Remote Sensing). These models should be developed at a global scale, in dynamically describing the spatial and temporal changes of soil organic matter cycle. Meanwhile, the further researches on models should be strengthen for providing theory basis and foundation in making policy of green house gas emission in China.

Design,Analysis,and Optimization of a CMOS Active Pixel Sensor

A three-transistor active pixel sensor and its double sampling readout circuit implemented by a switch capacitor amplifier are designed. The circuit is embedded in a 64 × 64 pixel array CMOS image sensor and success-fully taped out with a Chartered 0.35μm process. The pixel pitch is 8μm × 8μm with a fill factor of 57%, the photo-sensitivity is 0.8V/（lux · s） ,and the dynamic range is 50dB. Theoretical analysis and test results indicate that as the process is scaled down, a smaller pixel pitch reduces the sensitivity. A deep junction n-well/p-substrate photodiode with a reasonable fill factor and high sensitivity are more appropriate for submicron processes.

A Preliminary Study on the Establishment of AFLP Reaction System in Spinach

[Objective] This study aimed to establish an AFLP reaction system for spinach. [Method] Modified CTAB method was used for DNA extraction from six varieties of spinach. Experimental conditions in enzyme digestion and ligation, pre-amplification and selective amplification in the AFLP reaction system were analyzed and optimized. [Result] The results showed that： （1） enzyme digestion had better effects in the PCR instrument than in a water bath and it was not sensitive to the digestion time and DNA concentrations; （2） a total volume of 20 μl, containing 1.2 μl of Mg2＋ （25 mmol/L）, 1.6 μl of dNTPs （2.5 mmol/L） and 0.2 μl of Taq-polymerase （5 U/μl） was the optimal condition for pre-amplification and selective amplification reactions. [Conclusion] The AFLP system established in this study was stable and efficient, which provided a theoretical basis for AFLP molecular marker analysis of genetic relationship between spinach varieties and genetic breeding.

Study on the Influencing Factors and the Root Mechanism in Cutting Process of Prunus humilis(Bge). Sok

A procedure for cutting Prunus humilis（Bge）. Sok was comprehensively studied in this paper. It was found that the key factors involved in this procession were medium, rooting accelerator, concentration of rooting accelerator and type of shoot. The results showed that send was used as mediums; Treatment with 1 000 mg/L AST rooting powder No. 2 and semi-woody shoots were the optimal materials for cutting, and the rooting rate reached 88.1%. Anatomical study on rooting of Prunus hum#is（Bge）. Sok cutting has been carded out by the paraffin section method. The observation result shows that the adventitious root primordium of Prunus humili$（Bge）. Sok cutting belongs to the type of induced root primordium. The adventitiousroot primordium originates from the cross region of vascular cambium and pith rays.

First-principles Study of Field Emissions from Natrium-Encapsulated Boron-Nitride Nanotube in a Perpendicular Geometry

The field emission from pure boron-nitride nanotube and boron-nitride nanotube encapsu- lated with natrium atoms with the electric field perpendicular to the axis of nanotubes is simulated based on a self-consistent method using the density-functional formalism. It has been found that the nearly-free-electron states in boron-nitride nanotube would perform very well in field emissions after natrium atom encapsulation. The characters of total energy distribution curves are analyzed to seek the function of nearly-free-electron states in the field emission, with special attention to response of the emission current to the external electric field. At last, the perpendicular emission geometry is found to possess a very sensitive response degree which is supposed to be related to specific expansion orientation of the nearly-free-electron states in this system.

Comparison of the time-domain electromagnetic field from an infinitesimal point charge and dipole source

An electromagnetic field is generated through the accelerating movement of two equal but opposite charges of a single dipole. An electromagnetic field can also be generated by a time-varying infinitesimal point charge. In this study, a comparison between the electromagnetic fields of an infinitesimal point charge and a dipole has been presented. First, the time-domain potential function of a point source in a 3D conductive medium is derived. Then the electric and magnetic fields in a 3D homogeneous lossless space are derived via the relation between the potential and field. The field differences between the infinitesimal point charge and the dipole in the step-off time, far-source, and near-source zones are analyzed, and the accuracy of the solutions from these sources is investigated. It is also shown that the field of the infinitesimal point charge in the near-source zone is different from that of the dipole, whereas the far-source zone fields of these two sources are identical. The comparison of real and simulated data shows that the infinitesimal point charge represents the real source better than the divole source.

Optimization of the Fermentation Conditions of Sweet Oats by Response Surface Methodology

Objective] The purpose of this study was to evaluate the effects of five variables （steaming time, moisture content before inoculation, inoculation amount, fer-mentation temperature, fermentation time） on the sweetness of sweet oats, obtained the best fermentation conditions. [Method] Plackett-Burman （PB） was to evaluate the effects of five variables, and selected significant factors. The steepest ascent was used to approach the optimal response surface experimental area. The optimal fer-mentation condition was obtained by central composite design and response surface analysis. [Results] It was indicated that moisture content, inoculation amount and fer-mentation temperature had significant influences on the content of the reducing sugars. The optimal conditions of moisture content, inoculation amount and temper-ature were 45.26%, 0.014%（g/g） and 28 ℃, respectively. The predicted value of the reducing sugar content was 13.16 mg/g. [Conclusion] Under the optimal conditions, the content of the reducing sugars in the sweet oats could be up to 12.91 mg/g, which was on the whole consistent with the predictive maximum value.

Effects of Excessive Mg2+ on the Germination Characteristics of Crop Seeds

[ Objective ] The research aimed to reveal theeffects of excessive Mg^2＋ on the germination characteristics of maize and soybean. [ Method ] Eleven concentration gradients of Mg^2＋ including 0, 40, 80, 120, 160,200,240,280,320,360 and 400 mmol/L were set up to study the effects of different treatments on such indices as the germination potential, germination rate, fresh weight, dry weight, root length, plant height and stem diameter of maize and soybean. [ Result] With the increasing of Mg^2＋ concentration, the germination of maize delayed and the germination rate of soybean obviously decreased, reaching the significant difference at 0.05 level. When Mg^2＋ concentration increased, the fresh weight and dry weight of maize and soybean decreased, but maize and soybean showed some adaptability. The growth of radicles and seedlings in maize and soybean were obviously inhibited by Mg^2＋ , and atrophy and dysplasia phenomena appeared. [ Conclusion] Excessive Mg^2＋ stress has different effects on the germination potential and germination rate of different crops and has obvious poisoning effects on the root and stem growth of crops.

Elastoplastic response of functionally graded cemented carbides due to thermal loading

Finite dement formulations are used to simulate the evolution of the elastoplastic response of functionally graded cemented carbides （FGCC） due to thermal loading. The geometry of specimens is an axisymmetric solid cylinder with a two-dimensional gradient. The elastoplastic constitutive relationship is developed by constraint factors. Numerical results show that compressive stresses occur in the surface zone and tensile stresses in the cobalt rich zone when the temperature drops from the initial stress-free temperature of 800 to 0℃. The maximum value of the surface compressive stress is 254 MPa and the maximum value of the tensile stress is 252 MPa in the cobalt rich zones. When the cobalt concentration difference in the specimens is equal to or greater than 0.3, there is pronounced plastic flow in cobalt rich zone. When the temperature heats up from 0 to 800 ℃, the total plastic strain reaches 0.001 4. Plastic flow has a significant effect on the reduction of thermal stress concentration.

Response of Invasive Plant Alligatorweed to Salt Stress at Early Growth Stage

[Objective] The study aimed to investigate the early growth stage＇s response of invasive plant alligatorweed（Alternanthera philoxeroides） under salt stress.[Method] The alligatorweed was cultivated with four different NaCl concentrations 0（control）, 100, 200, 300 mmol/L diluted in 1/2 Hoagland＇s solution at early stage.During the period, we measured the number of nodes and leaves, length, fresh weight, dry weight and water content of stems to determine the effect of salt on alligatorweed growth. [Result] Compared with control, the node number, leaf number,length, fresh weight and dry weight of the stems significantly changed in NaCl solution, and the difference was positively related to NaCl concentration. We concluded that middle and high concentrations of NaCl significantly inhibited the growth of alligatorweed, by suppressing the node number, leaf number, length, fresh weight and dry weight of the stems. Among them, the stem length and fresh weight were more sensitive to NaCl stress. [Conclusion] The present result is helpful to understand the alligatorweed＇s adaptability to saline environment, and also helpful to prevent its invasion in such environment.

High-Responsivity ZnS Schottky Barrier Photodiode Array for Ultraviolet Imaging

A different approach,using the molecular beam epitaxy (MBE)-grown ZnS-based Schottky photodiode technology,is applied to fabricate an 8×8 photodiode array.The micro-processing procedures of this photodiode array including standard photolithography,a number of metallisation,wet-chemical etching and SiO_2 deposition for insulation are developed.The detector is characterized to have a cutoff wavelength at 340 nm and the photo-responsivity measurements on the pixels result an ultraviolet (UV) response as high as 0.15 A/W,corresponding to an external quantum efficiency of 55% in the visible-blind spectral ranging from 400 down to 250nm.Imaging tests indicate that this array is able to capture the intensity profile of a given UV light source with reasonably good capability.

Stable zinc oxide field emitter-based backlight unit for liquid crystal display

A zinc oxide ZnO field emitter-based backlight unit for liquid crystal display with a gated structure is fabricated by screen-printing processes.The measured anode field emission current density reaches 0.62 mA/cm2 when the applied gate voltage is 570 V.Part of the anode current is contributed by the secondary electron emission which is excited from the MgO layer inside the gate apertures on the gate plate. The average emission current density and luminance are 0.47 mA/cm2 and 1 250 cd/m2 respectively with a fluctuation of about 10% during the 1 000 min measurement.By a finite element method calculation the gated structure shows a good electron beam focusing property. The driving performance of the backlight unit is characterized by SPICE simulation tools and measured by the oscilloscope. Stable field emission line-by-line scanning and fast response characteristics of the backlight unit indicate its promising application in the liquid crystal displays.

Influential factors on the exchange rate of dissolved inorganic nutrients at the sediment-water interface in Jiaozhou Bay, China

Incubation experiments are carried out to study the exchange rates of dissolved inorganic nutrients including silicate, phosphate, ammonium, nitrite, and nitrate (vSiO3-Si, vPO4-P, vNH4-N, vNO2-N and vNO3-N) at the sediment-water interface in the Jiaozhou Bay. Major factors influencing the exchange rates are discussed in detail, which include the dissolved inorganic nutrient concentrations in porewater (Cpw), water and clay contents, and grain size of the sediments (CH2O, Cclay and GSsed). The results may provide insight into the dynamics of nutrient transport and the environmental capacity of nutrients in Jiaozhou Bay, and should be beneficial to solving the problems caused by excessive nutrient input this area.

Optical Rectification Induced by Al-Si Schottky Barrier Potential and Mechanism of Two-Photon Response

By observing two-photon response and anisotropy of the light-induced voltage in Al-Si Schottky barrier potential,it is certified from the experimental and theoretical analysis that the built-in electric field generated by the Schottky barrier potential will induce the phenomena of optical rectification in Si photodiode.Thus,it is deduced that there must be double-frequency absorption caused by phase-mismatch in the mechanism of two-photon response of Si photodiode.If the intensity of the built-in electric field is strong enough,the double-frequency absorption will be the main factor of the two-photon response,which is different from the conventional opinion that the two-photon response is just the two-photon absorption.

Advances in the Study of Protein Quality Traits and Main Influencing Factors of Wheat in China

Wheat, the third major grain crop in China, is an important source of hu- man proteins. Wheat quality and yield has a direct impact on the development of agricultural economy and food industry. Investigating and improving protein quality of wheat has become a key to solving the contradiction. This paper reviewed the exist- ing literature published at home and abroad, analyzed the present situation and ex- isting problems of wheat protein quality in China, summarized the latest research progress about genetic models, main influencing factors, and correlations between protein quality traits and other traits, discussed current issues in the improvement of wheat protein quality, and proposed suggestions for breeding high-quality wheat, aiming at providing theoretical basis for genetic improvement, planting structure ad- justment and efficient production of high-quality wheat.