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为了得到品质优良的元宝枫籽油产品，采用超临界二氧化碳萃取元宝枫籽油，以油脂萃取率为指标，通过单因素试验和响应面试验优化工艺条件，并对所得元宝枫籽油的脂肪酸组成、理化指标、甾醇和生育酚含量进行分析。结果表明：超临界二氧化碳萃取元宝枫籽油的最优工艺条件为原料粒度380~830 μm(20~40目)、二氧化碳流量28 L/h、萃取温度37 ℃、萃取压力44 MPa、萃取时间100 min，在该条件下油脂萃取率达（98.7±0.2）%；元宝枫籽油中神经酸含量高达9.34%，总不饱和脂肪酸含量为86.7%，各项理化指标均符合相关标准，总甾醇和总生育酚含量分别为988.1 μg/g和991.4 μg/g，综合品质优于正己烷萃取和低温压榨制取的油脂。综上，超临界二氧化碳萃取元宝枫籽油的萃取率高，产品品质优良，是一种绿色、高效的提油技术。In order to obtain high-quality Acer truncatum seed oil, the supercritical carbon dioxide extraction method was used to extract Acer truncatum seed oil, and the process conditions were optimized through single factor experiment and response surface methodology using the oil extraction rate as an indicator. The fatty acid composition, physicochemical indexes, and contents of sterol and tocopherol of the Acer truncatum seed oil were analyzed. The results showed that the optimal process conditions for supercritical carbon dioxide extraction of Acer truncatum seed oil were particle size 380-830 μm(20-40 meshes), carbon dioxide flow rate 28 L/h, extraction temperature 37 ℃, extraction pressure 44 MPa, and extraction time 100 min. Under these conditions, the oil extraction rate reached (98.7±0.2)%. The nervonic acid content in Acer truncatum seed oil was as high as 9.34%, and the total unsaturated fatty acid content was 86.7%. The physicochemical indexes of Acer truncatum seed oil were in line with the relevant standards, and its total sterol and total tocopherol contents were 988.1 μg/g and 991.4 μg/g, respectively. The comprehensive quality of Acer truncatum seed oil extracted by supercritical carbon dioxide extraction was better than that of the oil extracted by hexane extraction and low-temperature pressing. In summary, the supercritical carbon dioxide extraction method has a high oil extraction rate and excellent product quality, which is a green and efficient oil extraction technology.

Copyright of Science Technology & Engineering is the property of Chinese Society of Technology Economics 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.)

With the rapid development of silicon carbide (SiC) power devices and chip technology, the demand for grinding process of SiC wafers has become increasingly crucial due to the escalating requirements for physical strength, heat dissipation and size. Therefore, grinding process of SiC wafers has gradually become an important issue in manuscription processing. Due to its low fracture toughness, the SiC wafers are prone to cracking during grinding processes. It's a big challenge in achieving an efficient and high-quality grinding process for SiC wafers. Based on the process and principle analysis of SiC wafer grinding, the influence of four key parameters in the grinding process, i. e., grinding wheel size, feed rate, grinding wheel speed and chuck table speed on wafer surface edge breakage, were studied in this paper. The process of improving the processability of wafer by annealing is presented, and the surface integrity improving process of wafer is proposed. The study reveals the control method of wafer grinding processing surface quality, offered an efficient process route for reducing surface damage and improving the surface layer quality of chips, and verified the machining effect through experiments. The relevant results have important guiding significance for the wafer grinding process of hard and brittle materials. [ABSTRACT FROM AUTHOR]

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering 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 Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of 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 Journal of Modern Laboratory Medicine is the property of Journal of Modern Laboratory Medicine Editorial Department 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 Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic 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.)

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Copyright of Arid Land Geography is the property of Chinese Academy of Sciences, Xinjiang Institute of Ecology & Geography 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 Oil Drilling & Production Technology / Shiyou Zuancai Gongyi is the property of Shiyou Zuancai Gongyi Bianjibu 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 Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department 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 Journal of Jiangsu University (Natural Science Edition) / Jiangsu Daxue Xuebao (Ziran Kexue Ban) is the property of Editorial Department of Journal of Jiangsu University (Natural Science Edition) 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 Science Technology & Engineering is the property of Chinese Society of Technology Economics 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.)

The measurement sensor of the built-in sensor for VFTO is large in size and difficult to install, and cannot be applied to GIS in operation. In order to solve these problems, the VFTO measurement system for GIS metal flange holes is designed. The system adopts the scheme of combining FPC capacitor voltage divider and secondary resistance-capacitor voltage divider to realize VFTO measurement with external miniaturization of GIS. According to the size of the metal flange hole and the performance requirements of the measurement system, the structure and size of the FPC are designed, and the capacitance partial pressure probe is developed. In order to improve the performance of the measurement system, a broadband resistance-capacitance voltage divider is designed, and the matching resistance and the parameters of the coaxial cable are optimized through actual measurement. The results show that the bandwidth of VFTO measurement system is 22.45 Hz~111.45 MHz, and voltage division ratio is 112 790, indicating that the proposed system can accurately trace the source waveform and meet the requirements of VFTO measurement. [ABSTRACT FROM AUTHOR]

Copyright of China Journal of Oral & Maxillofacial Surgery is the property of Shanghai Jiao Tong University, College of Stomatology 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 Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department 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.)

When the frequency of the VFTO generated inside the GIS is consistent with the resonance frequency of the winding - type equipment, resonance overvoltage will be generated in the equipment and threaten the safe operation of the equipment. Therefore, it is necessary to analyze the spectral characteristics of the VFTO signal. In this study, a fast Fourier transform is proposed to perform spectrum analysis on VFTO waveform data generated when a field - disconnected isolator is closed. This study first introduces the principle of fast Fourier transform and the feasibility of VFTO spectrum analysis in detail, and describes the measurement system and experimental environment. From the result analysis, it can be found that the frequency component of the field measured VFTO signal is consistent with the frequency component proposed in the IEC 60071 - 1 : 2006 standard. The results verifies the feasibility of performing fast Fourier transform on the spectrum analysis of VFTO signals, and indicates the great applicability in practical engineering projects. [ABSTRACT FROM AUTHOR]

Copyright of China Population Resources & Environment is the property of Shandong Normal University 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 Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & 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 Hydrometallurgy of China is the property of Hydrometallurgy of China 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 Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department 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 Food & Machinery is the property of Food & Machinery 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.)

Aqueous extraction processing (AEP) is an environmentally friendly method to extract oil from various plants at a moderate temperature. However, the AEP also have several limitations. Firstly, the cream can be inevitably produced to form a sort of highly stable oil-in-water emulsion due to the adoption of water, stirring and centrifugation during processing. The formed emulsion become difficult to break completely, resulting in a huge challenge for the AEP performance. Secondly, the water that used in AEP normally serves as an extraction medium, but the usage of excessive water can result in the formation of thick suspension, which making it hard to directly release free oil. In general, the ratio of seed to water 1:5 kg/L or even higher was mostly chosen as the optimal ratio to eliminate the thick suspension as well as stable cream. However, the substantial consumption of water increased the treatment cost of subsequent wastewater after processing. A modified aqueous extraction of flaxseed oil was investigated using a low consumption of water under acidic wetting and drying, in order to enhance the AEP extracted yield of free flaxseed oil,while decrease the consumption of enzyme and water. The results showed that the yield of free oil was improved significantly due to the solubility effects of flaxseed protein under the pretreatment of acidic moisture-conditioning plus drying. In untreated flaxseed kernels,the free oil yield was only 18.95%±0.91%, while 71.29%±1.87% of the extracted oil went preferentially into the cream fraction. By contrast, the free oil yield increased to 83.27%±0.67% with the pretreatment of acidic moisture-conditioning plus drying. There was a vast increase in the amount of protein distribution in sediment phase under the pretreatment (from 33.34%±0.34% to 60.25%±0.44%), while the protein distribution in aqueous phase consequently decreased from 66.74±1.04% to 39.78%±0.66%. Processing conditions of aqueous extraction were also optimized by single-factor experiments, and the optimal parameters were obtained as follows: the extraction temperature was 50 ℃, pH value was 9.0, the ratio of flaxseed to water was 1:2.5 kg/L, extraction time was two hours. The recovery of free oil was achieved 82.88%±0.30% under the optimum conditions. Due to the increase of protein content in sediment phase and low flaxseed to water ratio of 1:2.5 kg/L, a part of oil was entrapped in sediment phase, which limited the further improvement of total oil yield. The sediment phase was further extracted by the aqueous phase plus deionized water,where the quality of deionized water was 50% quality of raw materials. The oil that distributed in sediment phase decreased from 3.97%±0.11% to 2.09%±0.04%after the second extraction. Subsequently, different enzyme and freeze-thaw were used to treat the demulsification of residual emulsion.The total yield of free flaxseed oil was 93.44%±0.29% after the residual emulsion was demulsified with papa in. After detecting the characteristic value of flaxseed oil from aqueous extraction processing and pressing extraction, the experiment came to a conclusion:There were no significant differences that observed on the refractive index, iodine value, conjugated diene value and conjugated triene value. Although the peroxide value of flaxseed oil by aqueous extraction processing was slightly higher than that by pressing extraction,it still well below the maximum value of cooking oil (10 mmol/kg).These findings demonstrate that the proposed pretreatment with low water consumption under acidic moisture-conditioning plus drying is suitable for the aqueous extraction of flaxseed oil. Therefore, this presented study can provide a promising technology for the extraction of flaxseed oil, where can increase the free oil recovery, while reduce the water consumption and the amount of enzyme. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department 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 Applied Mathematics & Mechanics (1000-0887) is the property of Applied Mathematics & Mechanics 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.)

Aiming al the problem of high damage and breakage rate of maize ears in traditional maize thresher, the method of agitation and impact on maize ears by coronal flat teeth mounted on high-speed spindle in threshing operation was studied. The threshing mechanism was improved and designed, and a new type of vertical roller maize thresher was put forward. The vertical rollers was used to thresh maize, and the trapezoidal cavity formed by conical cage core and outer barrel were combined, which made the force of maize in the threshing barrel uniform, and made full use of the gravity of the corn cobs and the downward axial force produced by the rollers to flow out quickly, so the separation of corn kernels and corncobs could be realized. The results indicate that the machine solves the problem that common maize threshers are easy to break and kernels. It can fully meet the requirements of high-dedusting, low-breaking, less-broken cobs and high-efficiency threshing operation of maize ears. It meets the domestic design standards. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department 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 investigate the application of fast track anesthesia in pediatric congenital heart disease and its effects on sedation and analgesia. Methods: 82 children with congenital heart disease who underwent surgical treatment in Affiliated Hospital of Guilin Medical College from June 2016 to May 2018 were selected. They were divided into control group(41 cases) and observation group(41 cases) according to the random number table method. The control group received routine anesthesia, while the observation group received fast track anesthesia. The dosage of anesthetic drugs, operative time, interruption time, cardiopulmonary bypass time,postoperative extubation time, hospitalization time, hospitalization expenses and complications were compared between the two groups.The sedation, analgesic effect at 12 h after operation of the two groups were observed. Results: The dosage of fentanyl and rocuronium in the observation group was significantly lower than that in the control group(P <0.05). There was no significant difference in intraoperative indexes between the two groups(P>0.05). Compared with the control group, the hospitalization time and extubation time of the observation group were shortened, and the hospitalization expenses were reduced(P<0.05). The sedative and analgesic effects at12 h after operation in the observation group were better than that in the control group(P <0.05). The incidence of postoperative complications in the observation group was 17.07%(7/41), which was lower than 39.02%(16/41) in the control group(P <0.05).Conclusion: Fast track anesthesia can reduce the dosage of fentanyl and rocuronium in pediatric congenital heart disease. It not only shortens postoperative extubation time and hospitalization time, reduces hospitalization expenses, but also improves sedative and analgesic effects, and it is safe and effective. [ABSTRACT FROM AUTHOR]

Copyright of Progress in Modern Biomedicine is the property of Publishing House of Progress in Modern Biomedicine 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 Chemical Engineering of Oil & Gas / Shi You Yu Tian Ran Qi Hua Gong is the property of PetroChina Southwest Oil & Gas Field Company 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 Research & Exploration in Laboratory is the property of Research & Exploration in Laboratory 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 Research of Environmental Sciences is the property of Research of Environmental Sciences Editorial Board 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 Progress in Modern Biomedicine is the property of Publishing House of Progress in Modern Biomedicine 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 investigate the clinical efficacy of modified lung-brain mixture (methylprednisolone sodium succinate injection + nikethamide injection + doxofylline injection) combined with routine treatment for chronic obstructive pulmonary disease complicated with type II respiratory failure. METHODS: Totally 130 patients with chronic obstructive pulmonary disease complicated with type II respiratory failure admitted into Chongqing Traditional Chinese Medicine Hospital from Dec. 2016 to Dec. 2018 were extracted to be divided into the control group and the observation group by the random controlled trial method, with 65 cases in each group. Both groups were given routine treatment, and patients in the observation group were treated with modified lung-brain mixture. The clinical efficacy and arterial blood gas analysis indexes [arterial partial pressure of carbon dioxide (PaCO2), arterial partial pressure of oxygen (PaO2)], tracheal intubation and ventilator-related complications were compared between two groups. RESULTS: The total effective rate of the observation group was 84.6% (55/65), significantly higher than that of the control group [60.0% (39/65)], and the difference was statistically significant (P<0.05). After treatment, the levels of PaCO2 and PaO2 in two groups were significantly improved compared with those before treatment, and the observation group was significantly better than the control group, the difference was statistically significant (P<0.05). The tracheal intubation rate of the observation group was 4.6% (3/65), significantly lower than that of the control group [15.4%( 10/65)], the difference was statistically significant (P<0.05). The incidence of ventilator-related complications in the observation group and the control group was 18.5% (12/65) and 16.9% (11/65), and the difference was not statistically significant (P>0.05). CONCLUSIONS: The efficacy of modified lung-brain mixture combined with routine treatment for chronic obstructive pulmonary disease complicated with type II respiratory failure is significant, which can improve patient’s symptoms. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering 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.)