The title complex, Zn(C24H13NO)2Cl21, has been synthesized by the reaction of zinc chloride with Schiff base ligand N-salicylidene-p-toluidine and its structure was determined by single-crystal X-ray diffraction. Th...The title complex, Zn(C24H13NO)2Cl21, has been synthesized by the reaction of zinc chloride with Schiff base ligand N-salicylidene-p-toluidine and its structure was determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group Cc with a = 14.896(3), b = 12.506(2), c = 15.352(3) A,β = 114.711 (4)°, V = 2598.0(8) A^3, C28H26ZnCl2N2O2, Mr = 558.80, Z = 4, Dc = 1 .429 g/cm^3,μ = 1.179 mm^-1, Flack parameter = 0.027(19), F(000) = 1152, R = 0.0709 and wR = 0.1041 for 3117 observed reflections (Ⅰ 〉 2σ(Ⅰ)). In complex 1, the center Zn ion is four-coordinated by two O atoms from two Schiff base ligands and two Cl atoms in a distorted tetrahedral geometry. Additionally, the thermal decomposition of complex 1 as well as its kinetic mechanisms and equations is studied under the non-isothermal integral and differential methods in air by TG-DTG curves.展开更多
In order to estimate intensity and direction of pressure acted on oil well in horizontal, this paper proposes an algorithm of ellipse fitting based on least square method for sections of oil well with ultrasonic imagi...In order to estimate intensity and direction of pressure acted on oil well in horizontal, this paper proposes an algorithm of ellipse fitting based on least square method for sections of oil well with ultrasonic imaging logging data. Five parameters about ellipse corresponding to the sections of oil well are extracted and their geometry deformations and direction are estimated. The tested results show that the fitting algorithm is robust and the estimating error of parameter is small, which have very important practical significance on processing the well logging.展开更多
The ultrasonovision image caused by the tool eccentricity can often present two pieces of vertical black strips in the Casing Well. To solve this problem, this paper proposes a correction algorithm of time eccentricit...The ultrasonovision image caused by the tool eccentricity can often present two pieces of vertical black strips in the Casing Well. To solve this problem, this paper proposes a correction algorithm of time eccentricity image based on ellipse fitting algorithm. This algorithm firstly utilizes borehole diameter data to fit ellipse and compute ellipse’s center, major axis, minor axis and inclination angle and other parameters, and then uses these parameters to correct eccentrical ultrasonovision time image. The tested results show that the algorithm can accurately fit ellipse and correct the eccentrical ultrasonovision time image, which is very important practical significance on processing the well logging.展开更多
The traditional Total-Variation algorithm has a good result to de-noise for noise image of small scale details, but it easily losses the details for the image with rich texture and tiny boundary. In order to solve thi...The traditional Total-Variation algorithm has a good result to de-noise for noise image of small scale details, but it easily losses the details for the image with rich texture and tiny boundary. In order to solve this problem, this paper proposes a Sobel-TV model algorithm for image denoising. It uses TV model to de-noise and uses Sobel algorithm to control smoothness of image, which not only efficiently removes image noise but also simultaneously retail information, such as edge and texture. The experiments demonstrate that the proposed algorithm is simple, practical and generates better SNR, which is an important value to preprocess image.展开更多
China has the world’s largest population and a large and critically important agricultural sector. Sixty-five percent of the Chinese population lives on paddy rice. However, drought disasters frequently afflict China...China has the world’s largest population and a large and critically important agricultural sector. Sixty-five percent of the Chinese population lives on paddy rice. However, drought disasters frequently afflict China’s rural population and threate n its food security. It is therefore of paramount importance to assess the drought risk of paddy in China. We establish a quantitative risk assessment model for the drought risk of mid-season paddy and regional-specific vulnerability curves, evaluate the drought risk of mid-season paddy, and compile a series of risk maps. The drought disaster risk rating results indicate that risk is highest in Northeast China, followed by Northwest China, North China, and South China, showing a decreasing trend from north to south. The mid-season paddy area of Northeast China has the highest mean risk index(0.58–0.71), followed by northwestern provinces such as Inner Mongolia and Xinjiang(0.5–0.6), while risk indices in provinces of North China such as Hebei and Shandong range from 0.3–0.5, and the southern provinces show a relatively low level of risk. This article presents the preliminary results of a scientific inquiry on where the high drought risk areas of mid-season paddy are and how high the risk is. These results provide a regional-specific basis for drought risk governance of paddy in China.展开更多
Horizontal attenuation total reflection-Fourier transform infrared spectroscopy (HATR-FTIR) is used to measure the FTIR of Fimbristylis miliacea (L.) Vahl seed and Fimbristhlis stauntonii Debeaux et Franch. seed. ...Horizontal attenuation total reflection-Fourier transform infrared spectroscopy (HATR-FTIR) is used to measure the FTIR of Fimbristylis miliacea (L.) Vahl seed and Fimbristhlis stauntonii Debeaux et Franch. seed. In order to extrude the difference between Fimbristylis miliacea (L.) Vahl seed and Fimbristhlis stauntonii Debeaux et Franch. seed, continuous wavelet transform (CWT) is used to decompose the FFIR of Fimbristylis miliacea (L.) Vahl seed and Fimbristhlis stauntonii Debeaux et Franch. seed. Three main scales are selected as the feature extracting space in the CWT domain. According to the distribution of FTIR of Fimbristylis miliacea (L.) Vahl seed and Fimbristhlis stauntonii Debeaux et Franch. seed, three feature regions are determined at every spectra band at selected three scales in the CWT domain. Thus nine feature parameters form the feature vector. The feature vector is input to the radial basis function neural network (RBFNN) to train so as to accurately classify the Fimbristylis miliacea (L.) Vahl seed and Fimbristhlis stauntonii Debeaux et Franch. seed. 110 couples of FI'IR are used to train and test the proposed method, where 60 couples are used as training samples and 50 couples are used as testing samples. Experimental results show that the accurate recognition rate between Fimbristylis miliacea (L.) Vahl seed and Fimbristhlis stauntonii Debeaux et Franch. seed is respectively 96% and 98% by using the proposed method.展开更多
文摘The title complex, Zn(C24H13NO)2Cl21, has been synthesized by the reaction of zinc chloride with Schiff base ligand N-salicylidene-p-toluidine and its structure was determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group Cc with a = 14.896(3), b = 12.506(2), c = 15.352(3) A,β = 114.711 (4)°, V = 2598.0(8) A^3, C28H26ZnCl2N2O2, Mr = 558.80, Z = 4, Dc = 1 .429 g/cm^3,μ = 1.179 mm^-1, Flack parameter = 0.027(19), F(000) = 1152, R = 0.0709 and wR = 0.1041 for 3117 observed reflections (Ⅰ 〉 2σ(Ⅰ)). In complex 1, the center Zn ion is four-coordinated by two O atoms from two Schiff base ligands and two Cl atoms in a distorted tetrahedral geometry. Additionally, the thermal decomposition of complex 1 as well as its kinetic mechanisms and equations is studied under the non-isothermal integral and differential methods in air by TG-DTG curves.
文摘In order to estimate intensity and direction of pressure acted on oil well in horizontal, this paper proposes an algorithm of ellipse fitting based on least square method for sections of oil well with ultrasonic imaging logging data. Five parameters about ellipse corresponding to the sections of oil well are extracted and their geometry deformations and direction are estimated. The tested results show that the fitting algorithm is robust and the estimating error of parameter is small, which have very important practical significance on processing the well logging.
文摘The ultrasonovision image caused by the tool eccentricity can often present two pieces of vertical black strips in the Casing Well. To solve this problem, this paper proposes a correction algorithm of time eccentricity image based on ellipse fitting algorithm. This algorithm firstly utilizes borehole diameter data to fit ellipse and compute ellipse’s center, major axis, minor axis and inclination angle and other parameters, and then uses these parameters to correct eccentrical ultrasonovision time image. The tested results show that the algorithm can accurately fit ellipse and correct the eccentrical ultrasonovision time image, which is very important practical significance on processing the well logging.
文摘The traditional Total-Variation algorithm has a good result to de-noise for noise image of small scale details, but it easily losses the details for the image with rich texture and tiny boundary. In order to solve this problem, this paper proposes a Sobel-TV model algorithm for image denoising. It uses TV model to de-noise and uses Sobel algorithm to control smoothness of image, which not only efficiently removes image noise but also simultaneously retail information, such as edge and texture. The experiments demonstrate that the proposed algorithm is simple, practical and generates better SNR, which is an important value to preprocess image.
基金This study was supported by the National Natural Science Foundation of China(41171402)the National Scientific and Technological Supporting Program of China(2008BAK50B07).
文摘China has the world’s largest population and a large and critically important agricultural sector. Sixty-five percent of the Chinese population lives on paddy rice. However, drought disasters frequently afflict China’s rural population and threate n its food security. It is therefore of paramount importance to assess the drought risk of paddy in China. We establish a quantitative risk assessment model for the drought risk of mid-season paddy and regional-specific vulnerability curves, evaluate the drought risk of mid-season paddy, and compile a series of risk maps. The drought disaster risk rating results indicate that risk is highest in Northeast China, followed by Northwest China, North China, and South China, showing a decreasing trend from north to south. The mid-season paddy area of Northeast China has the highest mean risk index(0.58–0.71), followed by northwestern provinces such as Inner Mongolia and Xinjiang(0.5–0.6), while risk indices in provinces of North China such as Hebei and Shandong range from 0.3–0.5, and the southern provinces show a relatively low level of risk. This article presents the preliminary results of a scientific inquiry on where the high drought risk areas of mid-season paddy are and how high the risk is. These results provide a regional-specific basis for drought risk governance of paddy in China.
文摘Horizontal attenuation total reflection-Fourier transform infrared spectroscopy (HATR-FTIR) is used to measure the FTIR of Fimbristylis miliacea (L.) Vahl seed and Fimbristhlis stauntonii Debeaux et Franch. seed. In order to extrude the difference between Fimbristylis miliacea (L.) Vahl seed and Fimbristhlis stauntonii Debeaux et Franch. seed, continuous wavelet transform (CWT) is used to decompose the FFIR of Fimbristylis miliacea (L.) Vahl seed and Fimbristhlis stauntonii Debeaux et Franch. seed. Three main scales are selected as the feature extracting space in the CWT domain. According to the distribution of FTIR of Fimbristylis miliacea (L.) Vahl seed and Fimbristhlis stauntonii Debeaux et Franch. seed, three feature regions are determined at every spectra band at selected three scales in the CWT domain. Thus nine feature parameters form the feature vector. The feature vector is input to the radial basis function neural network (RBFNN) to train so as to accurately classify the Fimbristylis miliacea (L.) Vahl seed and Fimbristhlis stauntonii Debeaux et Franch. seed. 110 couples of FI'IR are used to train and test the proposed method, where 60 couples are used as training samples and 50 couples are used as testing samples. Experimental results show that the accurate recognition rate between Fimbristylis miliacea (L.) Vahl seed and Fimbristhlis stauntonii Debeaux et Franch. seed is respectively 96% and 98% by using the proposed method.