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Due to the difficulty in predicting the surface roughness of roll grinding and its insufficient prediction accuracy, an intelligent prediction method of rolling surface roughness based on multi-process signals was proposed. Firstly, with the wheel speed, grinding depth, carriage speed and headstock speed as variables, a full-factor grinding experiment was carried out on the roll, and multi-process signals during the grinding process were collected, namely acoustic emission, vibration and spindle current signals, the surface roughness of the roll afier grinding was measured. Then, many eigenvalues of various signals in the time domain and frequency domain were extracted, and feature dimension reduction and fusion were carried out by using principal component analysis (PCA), and various types of feature inputs were constructed. Finally, the multi-layer perceptron (MLP) network was optimized by grid search method, and the prediction model of roughness was obtained, which realizes the intelligent prediction of the surface roughness of roll grinding. ‘The results show that the multi-signal scheme can provide more comprehensive and accurate information than single-signal scheme; the reduced dimensional fusion feature based on PCA ion effect of MLP networks, and the accuracy, Fl-score and mean deviation distance are 78. 16%, 0.777 6 and 0.29 respectively. [ABSTRACT FROM AUTHOR]

Objective: To analyze the risk factors of radioactive lung injury induced by intensity-modulated radiotherapy in patients with esophageal cancer. Methods: A total of 100 patients with esophageal cancer, who received intensity-modulated radiotherapy in the Affiliated Hospital of Qinghai Medical College from February 2015 to February 2018, were selected as research subjects.The data such as age, sex, smoking history, synchronous chemotherapy, karnofsky, tumor stage and radiation dosimetry factors V5, V10, V20,V30, and Dmean situation were collected. Univariate and multivariate Logistic regression analysis were used to analyze the risk factors of radioactive lung injury induced by intensity-modulated radiotherapy in patients with esophageal cancer. Results: Among the 100 patients,there were 27 cases of radioactive lung injury, the incidence was 27.00%, in which, there were 20 cases at grade 1 and 7 cases at grade 2.Univariate analysis showed that radioactive lung injury induced by intensity-modulated radiotherapy in patients with esophageal cance were related to karnofsk, V5, V10, V20, V30 and Dmean(P <0.05), but not related to sex, age, smoking history, synchronous chemotherapy and tumor stage(P>0.05). Multivariate logistic regression analysis showed that karnofsk <80 scores, V5>60%, V10>40%,V20>25%, V30>20%, and Dmean >10% were the independent risk factors of radioactive lung injury induced by intensity-modulated radiotherap in patients with esophageal cancer(P <0.05). Conclusion: The incidence of radioactive lung injury induced by intensity-modulated radiotherap in patients with esophageal cancer is higher. And it is closely related to karnofsk and radiation dosimetry factors such as V5, V10, V20, V30 and Dmean. In clinical work, the risk of radioactive lung injury can be reduced by controlling the dose of lung tissue. [ABSTRACT FROM AUTHOR]

In order to forecast the peak cutting force P′c of vertical cutting of conical picks under the conditions of plane cutting and dissymmetrical slotting (h1

In order to forecast peak cutting force of conical picks more accurately under conditions of plane cutting and symmetrical slotting，a new formula for calculating the peak cutting force and the formula which should satisfy the cutting boundary conditions are deduced theoretically. The derivation of the formulas were based on Evans' cutting model and assumed the stress distribution of conical surface of pick tip are different due to the clip effects of rocks when cutter cutting. Compared to other existing theoretical formulas，the calculation results are closer with the experimental value. In addition to considering the influence of some factors on the cutting force，such as half-cone angle θ of picks，tensile strength σt of rocks and friction coefficient f between picks and rocks，the brittleness index m of coal and rock is introduced. The formula should satisfy the cutting boundary condition which is represented by minimum limit of the ratio between cutting depth h and the vertical distance s from the loading position to the adjacent free border. That is smin/h，which mainly related to brittleness index m and almost unaffected by half-cone angle θ of picks. When m is 5 to 15，smin/h is between 2 and 3 and consistent with the existing experiments results. The derived formulas and conclusions can provide theoretical basis and guidance for the further analyzing and deducing of real peak cutting force containing more parameters of conical picks under actual mining condition. [ABSTRACT FROM AUTHOR]

Pyraoxystrobin is a methoxyacrylic fungicide with low toxicity, high efficiency and broad spectrum. It has good control effect on rice blast, rice sheath blight, cucumber downy mildew and cucumber powdery mildew. In order to explo re the degradation characteristics of pyraoxystrobin in water, the hydrolysis dynamics of pyrao xystrobin at different temperatures, pH values and t he photolysis dynamics under different illumination were studied, the hydrolysis and phot olysis prod ucts and pathways of pyraoxystrobin wer e studied by mass spectrometry with 13 C-pyraoxystrobin as control. The test results showed t hat the Pyraoxystrobin was difficult to hydrolyze in acidic and alkalescent aqueous solution (pH 8. 0). In alkaline aqueous solution (pH 10. 0-13. 0), t he hydrolysis dynamics of pyraoxystro bin was affected by temperature. With t he increase of temperature and pH values, the degradation rate was accelerated. The hydrolysis rate constants were linearly positively correlated with the pH values. Hydrolysis reaction was base-catalyzed reaction, and the higher temperatures, was the higher rate constants of base catalytic reaction were. Under indoor simulated sunlight and 30 °C, pyraoxystrobin was easy to photolysis, and t he photolysis reaction rate was increased with light intensity and ultraviolet intensity. Pyraoxystro bin was difficult to photolyze under the outdoor natural light at 13-19 °C . It was speculated that the ester bond was broken on the unlabeled atom C and an alkyl group (CH3) was removed in the hydrolysis process of pyraoxystrobin. The product might be (E)-2-[ 2-[[ 3-(4-chlorophenyl)-1-methyl-l H-pyrazol-5-oxy] methyl] phenyl]-3-methoxyacrylic acid (C21 H 19 ClN2 O4). The photolysis products was presumed to be 3-(4-chlo rophenyl)-5-((2-(4-methoxyfuran-3-yl) benzyl) oxy)-1-met hyl-l H-pyrazole after car bonyl hydrogenation on unlabeled atom C, dehydration and ring formation. The hydrolysis and photolysis products of zolexin ester and 13C-pyraoxystro bin ester were analyzed by mass spectrometry. It was speculated that the hyd rolysis process of zolexin ester may be the breaking of ester bond on unmarked C atom and the dehydration of an alkyl group to form C21 H19 ClN2 0 4. The photolysis process may be carbonyl hydrogenation and dehydration on unmarked C atom. After cyclization, 3-(4-chlorophenyl)-5-[[ 2-(4-methoxyfuran-3-phenyl] methoxy]-1-methyl-l H-pyrazole (C22 H 19 ClN2 O3) was formed. In this study, 13C-labelled pyraoxystrobin was used as internal standard, the degradation dynamics of zoxomycin in water were researched at different pH values and temperatures, and the photolysis of zoxomycin in water were researched under different light conditions. The hydrolysis and photolysis products and pathways of zoxomycin were analyzed and speculated in order to provide data for rational drug use, water source protection, ecological balance maintenance and food safety. [ABSTRACT FROM AUTHOR]

In order to achieve the accurate measurement and control of grinding force in the blade grinding process， a new measurement method of three-dimensional and orthogonal grinding force with mutual orthogonal and independent elastic elements was put forward， and a three-dimensional grinding force measurement platform of resistance strain was designed based on the high dynamic characteristics of grinding force. The performance of the measurement platform was verified through the mathematical derivation with the related formulas of material mechanics， the finite element simulation with Workbench and the actual testing experiments. The results showed that the above methods can effectively alleviate the dynamometer's inherent contradiction between its natural frequency and sensitivity， and significantly reduce the measurement platform's coupling degree among the grinding force measurements in different directions， which may provide technical support for achieving the real-time accurate detection of high frequency grinding force. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the effect of health education on the living quality of colorectal cancer patients after the operation. Methods: The patients with colorectal cancer who were taken the resection surgery in our hospital were selected and randomly divided into two groups. The 52 patients in the control group were treated by the conventional nursing, while the other 52 patients in the experimental group were treated with the health education besides of the regular nursing methods. Then the relative knowledge of disease, the postoperative complications, the hospitalization and the ostomy changes of patients in the two groups were observed and compared. Results: The relative knowledge of disease, the postoperative complications, the hospitalization and the compliance of treatment of patients in the experimental group were better than those of the patients in the control group with statistically significant differences(P<0.05). The self rehabilitation and changes of ostomy of patients in the experimental group were worse than those of the patients in the control group with statistically significant differences(P<0.05). Conclusion: It is suggested that the targeted health education should be well promoted to the clinical nursing for patients with intestinal cancers with the advantages of better effect and recovery. [ABSTRACT FROM AUTHOR]