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Objective: To analyze the image performance of colon innervation defect with multilayer spiral CT (MSCT) and clinical manifestations, summarize its image characteristics and make correct diagnosis. Methods: The clinical features of colonic innervations deficiency present with prolonged constipation and incomplete ileus. MSCT imaging data using GE gem energy spectrum, CT 750 HD, and Philips MSCT. 1 mm layer thickness, 1 mm layer spacing, tube voltage, 120 kV, automatic tube current from the diaphragm to the bilateral pubic joint. Scan in the natural state of the intestine (No bowel preparation, no cleansing enema and bowel cleansing), after scanning, conduct MPR 3D reconstruction at the CT workstation, and the reconstructed data were archived and analyzed in the PACS system. Clarify the intestinal location of the diseased segment, measure intestinal wall thickness of dilated segment and narrow segment respectively; measure intestinal tube length of diseased segment (narrow segment); observe intestinal peristalsis with multiple-stage MSCT; and observe intestinal blood transport through enhancement. Results: The clinical features of colon innervations defect was constipation and incomplete ileus. In this study group, there were 5 adult patients with colon innervations defect, and the lesion site was located in the spleen and descending colon respectively, among which the diseased segment was located in 3 cases and the spleen was located in 2 cases of colon; MSCT shows relative narrowing of the colon and expansion of the proximal colon; The intestinal wall thickness was normal in the diseased area, and the intestinal wall thickness of the dilated colon section was normal or somewhat thickened, and the thickened intestinal wall in this group is less than 0.9 cm; The intestinal length of the diseased segment in this group was somewhere between 4.3~8.6 cm. The MSCT enhancement scan of mesangic vessels and mesangial density showed no abnormal changes, and no abnormal enhancement of the colon wall in the diseased section, suggesting normal blood supply; MSCT enhanced scan showed rigidity and no peristalsis in the diseased segment, suggesting loss of peristaltic function in the diseased segment. Conclusion: Colonic innervations defect has imaging findings of characteristic post dilating stenosis and clinical features of prolonged constipation and incomplete obstruction in adults, The MSCT combined with clinical data was able to indicate the diagnosis of colonic innervations defect before surgery.

SAR offset and optical offset are important techniques for glacier movement monitoring, but there are few researches on 3D deformation by integrating images from different platforms. In this paper, large glaciers in The Shisha Pangma area of Nyalam County, Tibet from November 2019 to January 2021 were selected as the research area. Based on variance component estimation, Sentinel-1 and Landsat8 data of the study area were combined for three-dimensional glacier calculation. Optical images of the same period were selected for comparative analysis of the offset estimation results. At the same time, the accuracy of the method was evaluated by selecting the stable area, and the applicability and accuracy of the method in glacier movement monitoring were analyzed. The results show that the maximum velocity of the glacier is 21 cm/day in the east-west direction, 68 cm/day in the north-south direction, and 17 cm/day in the vertical direction. Compared with the glacier displacement results obtained from a single image, the multi-image joint algorithm can compensate for the incoherence of SAR data and the low quality pixel values of optical data, and obtain more complete and detailed glacier information and higher accuracy of monitoring results. This paper can provide reference and technical support for using data from different platforms to jointly monitor multi-dimensional and high-precision changes of mountain glaciers.

In order to achieve better starting performance of diesel engine in extreme low-temperature environment, the relevant parameters affecting the starting of diesel engine were researched. Through orthogonal simulation, the influence of environmental factors (intake pressure, intake temperature), design parameters (compression ratio, combustor reentrant ratio, nozzle diameter), control parameters (injection temperature, pilot injection quantity, start of main injection, main injection duration, injection interval between pilot injection and main injection) on diesel engine starting process under low-temperature conditions were studied. The key parameters affecting the starting process of diesel engine were extracted by range analysis. Meanwhile the parameters matching of each factor were studied by taking the cylinder pressure, the cylinder temperature and the instantaneous heat release rate as evaluation indexes. The results show that the environmental factors and control parameters have a higher degree of influence on the starting process of diesel engine. Intake pressure, intake temperature, start of main injection and main injection duration are the key parameters affecting the starting of diesel engine under low temperature conditions, and combination one is selected as the best parameter matching combination. The key parameters influencing the low temperature starting process of diesel engine are obtained, which provides a theoretical basis for improving the starting effect of diesel engine under low temperature.

Objective The Gouli area is one of the important gold and polymetallic belt in the East Kunlun Orogen. There is no research on lineament identification and mineral exploration based on multisource remote sensing data in the area. Methods In this paper, various enhancement techniques were employed on Landsat 8 OLI, GF-2 and DEM data to delineate structural lineaments. Meanwhile, information on geological, mineral and geochemical anomalies was combined to define prospecting targets in the Gouli area. Results The results show that (1) The tectonic framework of the study area can be divided into two regions by the boundary of Kaketeer-Seride. The lineament in the northern region is most developed in the NNE direction, followed by the near-EW direction, and less distributed in the NW and NE directions. The lineament in the southern region is mainly developed in the near-EW direction, and the NW to NE directions are less distributed. (2) The gold ore is controlled by lineaments. (3) The areas of densely distributed and intersected lineaments, as well as the areas connected by different colors on remote sensing images, are favorable locations for gold mineralization. Finally, based on the comprehensive analysis of multiple geological information and remote sensing interpreted tectonic information, four prospecting targets were identified in the study area and verified in the field. Conclusion This study proves that multisource remote sensing data can better identify the spatial structure characteristics of surface tectonics, which can provide a reference and basis for prospecting new deposits in the Gouli area.

Carbon emission from the coal-burning power plant is the main source of CO2 emitted in the China’s energy industry. Biomass power generation is deemed to be a carbon-neutral or even carbon-negative mode. Therefore, the development of coal coupled biomass gasification technology for power generation can help to achieve a coal substitution and carbon emission reduction and is a realistic and feasible path for maintaining a low-carbon coal power generation. In this context, an overview of three coal coupled biomass power generation technologies (the coal/biomass direct combustion of coal and biomass, the coal/biomass direct combustion coupled in parallel mode, and the coal direct combustion coupled with biomass gasification) has been conducted in this study. The characteristics of the above three technologies have been analyzed. Future development trends in the coal-burning coupled biomass gasification power generation technology have been put forward. The physicochemical adaptability of the feedstock and the influence of the feedstock on the gasifier are also studied based on the coupled gasification power generation technology. This work has emphasized the technological process of coal coupled biomass gasification power generation technology, including biomass transportation system, gasifiers (the technical characteristics, technical challenges and development direction of circulating fluidized bed gasifier (CFB), double fluidized bed gasifier (DFB), downdraft fixed bed gasifier, updraft fixed bed gasifier, crossdraft fixed bed gasifier and chain grate have been analyzed), gas cooling system, gas-pressurized transportation system, combustion system and gas purification system. The energy utilization efficiency analysis, economic analysis and environmental benefit analysis of the technology have been carried out. The analysis obtained would provide a theoretical reference and technical support for the research and application of coal-coupled biomass power generation technology. In addition, a series of national policies to promote coal coupled biomass gasification power generation technology and the current successful cases of coal coupled biomass gasification power stations are also presented. Finally, the challenges and future development of coal coupled biomass power generation technology have been prospected.

In order to make scientific and rational use of waste rock and soil in mining areas, guide its classification and discard and reconstruct high quality reclaimed soil, the loess parent material in the Pingshuo opencast mining area is used as a control to analyze the differences in physical and chemical properties of different types of rock and soil layers, and the source control of land reclamation is conducted from the source of the reclaimed soil parent material. It may provide a basis for land reclamation and ecological restoration in opencast coal mines. Combining the analysis results of the single nutrient content and beneficial trace element content, with the help of the modified Nemero comprehensive index method, the fertility quality of each rock and soil layer is comprehensively evaluated. With the single factor quality index method, the environmental quality of each rock and soil layer is also evaluated. The comprehensive fertility coefficient of each rock and soil layer is in the range of 0.40 to 1.26, which is barren or general. The organic matter or total nitrogen content of the two gangue layers in the Anjialing Mine, the total potassium content of the upper shale layer in the Anjialing Mine, and the total phosphorus content of the carbonaceous mudstone layer in the East Opencast Mine are rich, which are significantly higher than those of the loess parent material layer. The fine sandstone layer at the bottom of the East Opencast Mine and the marl layer in the Anjialing Mine have excessively high sulfur content, and the former cadmium element environmental quality index is 1.05, which is a slight pollution level. The pH value of the fine sandstone layer at the bottom of the Anjialing Mine is as low as 4.25 and the acidity is too high. Most of the rock and soil layers in the Pingshuo opencast mine are of good environmental quality but poor comprehensive fertility quality. The rock and soil layers with safe environmental quality, which have rich individual nutrient contents and are easily weathered, can be used as the alternative material for rebuilding the reclaimed soil. It is conducive to improving the quality of the reclaimed soil and improving the productivity of reclaimed soil in a short time.

To solve the combination explosion problem and the blind searching problem in assembly sequence planning of complex products, an assembly sequence planning method based on composite algorithm is proposed. In the composite algorithm, a sufficient number of feasible assembly sequences are generated using formalization reasoning algorithm as the initial population of genetic algorithm. Then fuzzy knowledge of assembly is integrated into the planning process of genetic algorithm and ant algorithm to get the accurate solution. At last, an example is conducted to verify the feasibility of composite algorithm.

Riboflavin (vitamin B2), a safe and non-toxic food additive, plays an important physiological role in plant growth, development and stress resistance. In this study, we investigated the effects of exogenous riboflavin on the postharvest quality maintenance of pak choi (Brassica rapa subsp. chinensis). Pak choi was treated at postharvest with different concentrations of riboflavin (0, 200, 400, 600, and 800 μmol/L) and evaluated for color, chlorophyll content, chlorophyll metabolism-related gene expression and antioxidant enzyme activity. The results showed that 400 μmol/L riboflavin treatment effectively maintained the quality of postharvest pak choi, mainly by 1) reducing the expression of chlorophyll catabolism-related genes (BrNYC1, BrPPH, BrPAO, and BrSGR1/2) to delay chlorophyll degradation, 2) reducing the total bacterial count on the surface of pak choi leaves to reduce pathogenic spoilage, and 3) upregulating the expression of antioxidant enzyme genes (BrPOD, BrSOD and BrCAT) and enhancing the antioxidant enzyme activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) to increase antioxidant activity. In addition, riboflavin treatment maintained high levels of antioxidants (ascorbic acid and total phenolics), thereby increasing the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity and reducing the production of malondialdehyde (MDA). These findings are helpful to understand how riboflavin affects the postharvest quality of leafy vegetables, which is of reference significant for improving the postharvest commercial value and quality of leafy vegetables.

Objective: To study the classification and individualized treatment of the terminal phalanx of thumb duplication., Methods: From Apr. 2003 to Dec. 2012, 76 patients with 77 involved thumbs duplication at the level which is distal to the interphalangeal joint were retrospectively studied. Based on the morphology (the nail width and the thumb circumference) and the deviation of the thumb, we classified the terminal phalanx of thumb duplication into 5 types as Type A (no bony connection called floating thumb), Type B(asymmetry and no deviation), Type C(asymmetry and deviation), Type D (symmetry and no deviation) and Type E(symmetry and deviation). Different surgical procedures were selected according to different types. Simple excision of the smaller thumb was adopted for Type A case. Removement of the smaller thumb (usually the radial) and of the collateral ligament of the interphalangeal joint were selected for Type B. Removement of the smaller thumb (usually the radial) and reconstruction of the collateral ligament of the interphalangeal joint, as well as corrective osteotomies at the neck of the proximal phalanx were performed for Type C. The modified Bilhaut-Cloquet procedure with reconstruction of the collateral ligament of the interphalangeal joint were adopted in Type D. The classical Bilhaut-Cloquet procedure, or the modified Bilhaut-Cloquet procedure with reconstruction of the collateral ligament of the interphalangeal joint and corrective osteotomies at the neck of the proximal phalanx were performed in Type E. The results were assessed by an evaluation form for thumb duplication by the Japanese Society for Surgery of the Hand., Results: According to our new classification standard, there were 3 cases with Type A duplicated thumbs, 36 with Type B, 13 with Type C, 15 with Type D, 10 with Type E. All the 76 patients underwent the individualized surgical treatment. The patients were followed up for 6-60 months. According to the evaluation form, excellent results were achieved in 66 thumbs, good in 9 thumbs and fair in 2 thumbs., Conclusions: The new classification could comprehensively describe the clinical features of the terminal phalanx of congenital thumb duplication. Individualized therapy, including basic and repeated surgical procedure could be adopted for each type with satisfactory results.