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This article analyzed the feasibility of using wax oil for vulcanization during the operation of a fixed bed residue hydrogenation unit. A certain company has adopted whole process VGO sulfurization technology for the first time to pre sulfurize fresh catalysts. Whole process sulfurization can save 16 hours of equipment operation time, reduce the amount of diesel used during equipment operation, and reduce the production of unqualified VGO by 720 tons. In the low-temperature vulcanization stage, the sulfur uptake rate of VGO sulfurization is higher and the sulfurization is more uniform. A comparative analysis was conducted on the catalytic performance of VGO sulfurization and staged sulfurization. Under the same process conditions and feedstock properties, both catalysts vulcanized in different ways have the same high impurity removal rate. The whole VGO sulfurization catalyst has the same activity as the staged sulfurization catalyst. The catalyst using whole VGO sulfurization has a relatively long operating cycle, indicating that the stability of the whole VGO sulfurization catalyst is relatively high. Whole VGO sulfurization has many advantages such as simple operation, resource conservation, and reducing activity. It has reference significance for other similar devices and provides valuable experience for optimizing pre vulcanization operations in future similar devices. [ABSTRACT FROM AUTHOR]

Objective On-line gas chromatograph is the key analysis equipment to realize natural gas energy measurement. It is of great significance to carry out the research on the adaptability of domestic on-line gas chromatograph, and to break the technical barriers of imported on-line gas chromatograph and to realize the localization of instruments and equipment. Method The gas standard material was analyzed by on-line gas chromatograph and the field application test was carried out, analyze and evaluate the effectiveness, separation degree, reproducibility, accuracy and stability of the prototype. Results The prototype can effectively analyze the content of N2, CO2, C1-C6 hydrocarbon components in the gas, and the analysis period is not more than 2 min; resolution R=2.0 for iC4 and nC4, quantitative repeatability RSD≤1.0% for nC4; the stability of the prototype operation for 4 hours is 3.0%; the relative deviation from the actual natural gas samples obtained by imported on-line gas chromatograph is not more than 0.1%. Conclusions The developed prototype can basically meet the needs of natural gas energy measurement, which provides a technical reference for the comprehensive implementation of natural gas energy measurement and the localization of on-line gas chromatograph in China. [ABSTRACT FROM AUTHOR]

Copyright of Geography & Geographic Information Science is the property of Geography & Geo-Information Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Imaging Science & Photochemistry is the property of Imaging Science & Photochemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To investigate the difference of efficacy between single-port and four-port laparoscopic cholecystectomy. A retrospective analysis was performed on the clinical data of laparoscopic cholecystectomy (single-port group) and four-port laparoscopic cholecystectomy (four-port group) performed in the Department of Biliary and Pancreatic Surgery, Renji Hospital Affiliated to Medical College of Shanghai Jiaotong University from June 2018 to August 2019. Including operation time, abdominal drainage tube indwelling rate, surgical plan change rate, surgical blood loss, postoperative complication rate (biliary leakage, bleeding, wound infection), hospital stay, hospitalization cost, use rate of analgesic drugs 24 hours after operation and postoperative satisfaction, etc. The operation time of the single-port group was significantly longer than that of the four-port group [(42.48 依6.66)min Vs (32.18 依7.08)min], and the abdominal drainage tube indwelling rate in the single-port group was significantly lower than that of the four-port group (1.67% Vs 21.67%), with statistical significance (P<0.05). The hospital stay of the single-port group was shorter than that of the four-port group [(2.22依0.65) days Vs (2.71依0.57)days], the hospitalization cost of the single-port group was higher than that of the four-port group [(2.19依0.17)ten thousand yuan Vs (1.81依0.14) ten thousand yuan], and the use rate of analgesic drugs 24 hours after operation in the single-port group was lower than that of the four-port group (4.17% Vs 16.67%). The postoperative satisfaction score of the single-port group was higher than that of the four-port group [(4.68依0.64)scores Vs (4.47依0.68)scores], and the differences were statistically significant (P<0.05). There were no differences between the single-port group and the four-port group in the surgical blood loss, surgical plan change rate and postoperative complications (P>0.05). Single-port laparoscopic cholecystectomy has light postoperative pain, fast recovery, and no significant difference in surgical safety compared with traditional four-port laparoscopic cholecystectomy. At the same time, single-port laparoscopic cholecystectomy has high satisfaction, which is worthy of clinical promotion. [ABSTRACT FROM AUTHOR]

To investigate the changes of QRS-T angle before and after percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI) and its value in evaluating the prognosis. 115 MI patients who underwent PCI in our hospital from July 2016 to August 2018 were selected as the treatment group and divided into low,middle and high narrow sub-groups and followed by 12 months follow-up,while 38 non-AMI patients underwent physical examination were selected as the control group. The general data and preoperative QRS-T angle between the two groups, the changes of QRS-T angle within 24 hours after operation and the cumulative occurrence of major adverse cardiovascular events (MACE) in 12 months were compared between the two groups. Pearson model and Cox regression model were used to analyze the correlation between QRS-T angle and MACE and; the risk factors of MACE. QRS-T angel before PCI was significantly higher in the treatment group than the control group and increased with disease severity both before and after PCI. QRS-T angel decreased 24 h after PCI among the three sub-groups (P＜0.05). 12 months'MACE increased significantly in high narrow group than the other two groups χ²=14.12, P=0.001 . Gensini score and QRS-T angel before and 24 h after PCI were positively correlated with MACE significantly (P＜0.05). Multivariate Cox regression showed Gensini score (HR=1.015, P=0.024) and QRS-T angel (HR=1.009, P=0.027) before PCI were risk factors of MACE. In AMI patients, Gensini score and QRS-T angel before PCI are risk factors of MACE. QRS-T angel before PCI has a good predictive value for the prognosis of acute myocardial infarction. [ABSTRACT FROM AUTHOR]

BACKGROUND: Although cocktail therapy is widely used to relieve pain after total knee arthroplasty, the analgesic effect of different combination schemes has not been fully confirmed. OBJECTIVE: To observe the efficacy of cocktail therapy on analgesia after total knee arthroplasty with enhanced recovery after surgery program. METHODS: Sixty patients with severe knee osteoarthritis who underwent unilateral total knee arthroplasty at Tianjin Hospital from January to May 2019 were enrolled. According to the principle of double-blind randomization, they were divided into two groups, 30 cases in each group. Patients in the trial group were injected with cocktail formula drugs around the joints in the operation, while patients in the control group did not receive any treatment. Static pain visual analogue scale scores of knee joints at 6, 12, 24, 48, and 72 hours, the maximum flexion of the knee joint at 48 and 72 hours, the initial time of the straight legraising, and postoperative opioid remedy analgesia rate and postoperative complications were compared between the two groups. RESULTS AND CONCLUSION: (1) The visual analogue scale scores of the trial group were significantly lower than those of the control group at 6 and 12 hours after operation (both P < 0.001), and the postoperative analgesic rate of opioids was significantly lower in the trial group than that of the control group (P < 0.001). (2) There were no statistically significantly differences in the preoperative general data, visual analogue scale scores at 24, 48, and 72 hours, knee maximum flexion at 48 and 72 hours, the time of the straight leg-raising, and postoperative complications (both P > 0.05). (3) The results indicate that cocktail therapy in total knee arthroplasty is safe and effective for early postoperative analgesia with enhanced recovery after surgery program. [ABSTRACT FROM AUTHOR]

BACKGROUND: Tropisetron hydrochloride has been shown to effectively reduce postoperative nausea and vomiting in patients undergoing proximal femoral nail antirotation fixation, and it is safe and effective. At present, the use of tropisetron in this operation is mainly added to patient controlled intravenous analgesia or intravenous drip after the operation. However, the comparison of two administration methods of tropisetron is rarely reported. OBJECTIVE: To investigate the effectiveness and safety of different administration methods of tropisetron hydrochloride for reduction of postoperative nausea and vomiting in proximal femoral nail antirotation. METHODS: Ninety patients with intertrochanteric fracture of femur who underwent proximal femoral nail antirotation admitted in Shantou Hospital of Traditional Chinese Medicine from July 2018 to March 2020 were randomly divided into two groups (n=45). Patients in the group A (intravenous drip administration group) were given tropisetron hydrochloride 5 mg + normal saline 100 mL by intravenous drip immediately after the operation, and the patient controlled intravenous analgesia pump (tropisetron hydrochloride was not added into the pump) was used. Patients in the group B (patient controlled intravenous analgesia pump group) were given 100 mL normal saline by intravenous drip immediately after the operation, and the patient controlled intravenous analgesia pump (5 mg tropisetron hydrochloride was added into the pump) was used. The pain score, sedative score, postoperative nausea and vomiting score and postoperative nausea and vomiting incidence at 1, 6, 12, 24, and 48 hours after the operation of two groups were counted and compared. RESULTS AND CONCLUSION: (1) The pain score and sedative score of the two groups were not statistically significant (P > 0.05) at various time points. (2) The postoperative nausea and vomiting score and postoperative nausea and vomiting incidence of group A were significantly less than those in the group B at 1 and 6 hours after the operation (P < 0.05). The differences in postoperative nausea and vomiting score and postoperative nausea and vomiting incidence of the two groups were not statistically significant at 12, 24, and 48 hours after the operation (P > 0.05). (3) There was no significant difference in incidence of adverse reactions between the two groups (P > 0.05). (4) Compared with added tropisetron hydrochloride to patient controlled intravenous analgesia pump, postoperative intravenous drip administration of tropisetron hydrochloride can quickly reduce the occurrence of nausea and vomiting after proximal femoral nail antirotation fixation. [ABSTRACT FROM AUTHOR]

In China, the planting area of peanut is 5 million hm² and the yield is 17 million kg. Seed shelling is an important part of peanut seed preparation before sowing, the quality of peanut seed after shelling affects the emergence, growth and yield of peanut. At present, peanut seed shelling is mainly based on the shape characteristics of peanut pods, mechanical actions such as kneading, extrusion and impact are used to crack and break the peanut pods to complete the shelling. However, the existing peanut shellers have some problems, such as low rate of shell removal, high rate of seed damage and poor adaptability to peanut varieties. In order to solve the above problems, a cone disc shelling mechanism for peanut seeds was designed. Taking Huayu 23 peanut as the experimental object, the EDEM software was used to simulate the shelling process of peanut pods, and the optimal structure parameters of the cone type shelling mechanism were obtained by simulation analysis and prototype testing. The best structural parameters of the shelling mechanism were obtained through simulation analysis and prototype test, that is, the inclination angle of the lower cone was 25°, and the inclination angle of the upper cone was 30°. In order to further reduce the damage rate of peanut seeds, the rubber spines were pasted on the shell surface of the upper and lower cones of the machine. The rotation speed of lower cone, the minimum shelling clearance and number of rubber bumps were taken as experimental factors, threshing rate and damage rate of peanut were taken as response values, single-factor test and Box-Behnken test were conducted. ANOVA was performed on the test results by Design-Expert 8.0.6 software, and the regression models of the threshing rate and the damage rate between the rotation speed of lower cone, the minimum shelling clearance, the number of rubber bumps were established. The optimal combination of the three factors were obtained by the dual objective optimization method, that was the rotation speed of lower cone 270 r/min, the number of rubber bumps within one squire meter 5 500 and the minimum shelling clearance was 11 mm，respectively, at this time, the highest predicted value of the threshing rate was 97.95%, and the lowest predicted value of the damage rate was 3.19%. The comparative experiment results showed that compared with the drum type sheller for peanut seeds, the threshing rate of the cone disc sheller without rubber spines was slightly higher and the damage rate was slightly lower. The threshing rate of the cone disc sheller with rubber spines was increased by 2.03 percentage points, and the damage rate was reduced by 0.67 percentage points..According to the fatigue damage analysis of rubber spines, after 90 hours of shelling operation, the rubber skin was seriously worn and the shelling quality was reduced, it should be replaced in time. The research results can provide reference for the development and improvement of peanut seeds sheller. [ABSTRACT FROM AUTHOR]

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To explore the relationship between serum soluble triggering receptor expressed on myeloid cell-1(s TREM-1), pulmonary function index and pulmonary infection in patients with lung cancer after operation and their predictive value.Methods: Clinical dataes of 115 patients with lung cancer treated surgically in our hospital from January 2016 to January 2019 were retrospectively analyzed. The patients were divided into infection group(n=28) and non-infection group(n=87) according to whether pulmonary infection occurred 72 hours after operation. The clinical data, serum levels of s TREM-1, procalcitonin(PCT), preoperative lung function index [forced expiratory volume in the first second(FEV1), peak expiratory flow(PEF)] at 6 hours after operation were compared between the two groups. Logistic analysis of risk factors of infection in patients with lung cancer after operation was analyzed. The receiver operating characteristic(ROC) curve was used to evaluate the predictive value of s TREM-1, FEV1 and PEF in patients with lung cancer after operation. Results: The proportion of ICU admission in the infected group was higher than that in the non-infection group,and the proportion of TNM stage IV in the infected group was higher than that in the non-infection group(P<0.05). Serum levels of s TREM-1 and PCT were higher in the infection group than those in the non-infection group at 6 hours after operation, and the levels of preoperative FEV1 and PEF were lower than those in the non-infection group(P<0.05). The results of sputum culture in infection group showed that 17 cases were G-bacteria, accounting for 60.71%; 10 cases were G+bacteria, accounting for 35.71%; and 1 case was fungi,accounting for 3.57%. Bivariate multivariate logistic analysis showed that the increase of serum s TREM-1 level at 6 hours after operation, the decrease of preoperative FEV1 and PEF, and the admission to ICU after operation were independent influencing factors of infection in patients with lung cancer. The area under the combined prediction curve was 0.850(95% CI: 1.350-1.745, P=0.000), and the sensitivity and specificity were 91.3% and 80.6% respectively, which were better than the single prediction efficiency of s TREM-1, FEV1 and PEF. Conclusion: The increase of s TREM-1 level and the decrease of preoperative FEV1 and PEF levels are closely related to pulmonary infection in patients with lung cancer after operation. The combined analysis of s TREM-1, FEV1 and PEF has a high predictive value in predicting the occurrence of pulmonary infection in patients with lung cancer after operation. [ABSTRACT FROM AUTHOR]