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Copyright of Shandong Medical Journal is the property of Shandong Medical Health Newspapers 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 Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering 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 Computer Engineering & Applications is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. 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 Computer Engineering & Science / Jisuanji Gongcheng yu Kexue is the property of Computer Engineering & Science 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 Engineering Geology / Gongcheng Dizhi Xuebao is the property of Journal of Engineering Geology 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 Energy Chemical Industry is the property of Energy Chemical Industry 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.)

High planting frequency and seedling falling stability can be preferred during operations in a seedling-taking device of rape matrix seedling transplanter in recent years. In this study, a counter-roll seedling taking device was proposed for the rape matrix block seedling transplanter. A performance test was also carried out to optimize the structure and working parameters for the stable operation of the roller seedling taking device. A stability analysis was then performed on the seedling taking and planting process, in order to combine with the operating characteristics of matrix block seedling transplanter, according to the requirements of planting agronomy. A single-factor bench test was conducted using the self-developed rape matrix block seedling transplanter, where the rape seedling carrier matrix block was taken as the operation object in the suitable planting period. Subsequently, a systematic investigation was made to clarify the influence of structural parameters on the success and synchronization rate of seedling collection. Specifically, the optimal ranges were achieved, where the seedling carrier angle, the diameter at the bottom end of the roller, and the rotation speed of the roller were determined as 30.0°-34.0°, 25.5-29.5 mm, and 1.8-3.6 r/s, respectively. A three-factor and three-level quadratic orthogonal test was carried out to verify the structural parameters after optimization. The results showed that the performance of seedling collection was the best when the angle of the seedling carrier was 30.7°, the diameter of the roller bottom was 26.4 mm, and the roller speed was 2.2 r/s. Furthermore, the success and synchronization rates of the seedling collection were 94.10%, and 95.14%, respectively, in the bench test. In addition, a high-speed camera was used to extract the trajectory of seedling picking in the rape seedling carrying matrix block at the planting stage, in order to determine the influence of roller diameter on the seedling picking trajectory. Consequently, the average change in the bottom angle of the seedling carrying matrix block during the actual seedling picking was 14.18° under the optimal combination of seedling picking parameters. There was an average angle error of 3.42°, compared with the theoretical value of 17.6°. The variation was attributed to the overall size of the seedling carrier matrix block, and the working vibration of machines and tools in the actual seedling picking. There was also a slight deviation between the bottom angle of the seedling carrier matrix block before and after seedling picking in the theoretical analysis. A field experiment was carried out under a better combination of working parameters, in order to verify the operation performance of the whole machine. It was found that the success and synchronization rate of seedling taking were 89.84%, and 92.01%, respectively, which fully met the performance requirements of the seedling taking device of rape matrix block seedling transplanter. The improved structure can also be optimized in the transplanter seedbed finishing device for better matching with seedling taking device in the follow-up. The finding can provide a strong reference to designing the seedling taking device in a rape matrix block seedling transplanter [ABSTRACT FROM AUTHOR]

Separating seedling is highly lacking to implement the planting operation in mechanized transplanting of rapeseed substrate block seedlings. In this study, a novel separating seedling device with a pair of rollers was designed in a transplanter, particularly for the rapeseed substrate block seedlings using a degree of freedom (DOF) constraint of a mechanical system. Two stages were divided in the working process of the device, including pneumatic seedling separation and counter-roller seedling collection. As such, the combination of pneumatic seedling separation and counter-roller wheel was used to realize the stable and synchronous seedling separation of each row. Kinematic models were also constructed for the separate seedling and picking stage in the process of transplanting. Some key parameters were optimized as follows: the linear speed of the synchronous belt ranged from 66.67 to 133.33 mm/s, while the roller speed ranged from 192.46 to 294.67 mm/s, and the angle of the seedling platform was 30° to 45°. A quadratic rotation orthogonal experiment was carried out to explore the effects of the linear speed of synchronous belt and roller, as well as installation angle of seedling loading platform on the success and synchronization rate in seedling picking. The results showed that the performance of picking seedlings was better than before, when the speed of the synchronous belt was 120.9 mm/s, the linear speed of the roller was 238.2 mm/s, and the angle of the seedling platform was 31.9°. The success rate and synchronization rate were also 93.42% and 94.42%, respectively. It was found that with the increase of the angle of the seedling platform in the bench test, the conveying fluency of seedling substrate block decreased significantly, together with some toppling of seedling, where the seedling substrate block moved from the synchronous belt to the seedling platform. The reason was that the stability of the seedling dropped significantly, as the angle of the seedling platform increased, thereby easy to topple, where there was an obvious decrease in the distance between the seedling substrate block and the bottom of the ditch. Correspondingly, the seedling was easy to cause the collapse, whether the linear speed of the synchronous belt was too high or low. The error was accumulated constantly, as the number of seedlings increased, further leading to the missing planting and heavy load. Once the horizontal speed of the roller was consistent with the forward speed of a machine, the speed of the seedling dropping was achieved at zero, while the stability of the seedling was much better. But when the speed changed greatly, the stability of the seedling picking using a counter roller was getting worse, while the seedling dropping was easy to occur dumping. In any way, a field experiment demonstrated that the success rate of collection seedlings was 88.69%, and the synchronous rate of collection seedlings was 92.72%, meeting the technical requirements of separating seedlings of rapeseed substrate block seedlings transplanter. The finding can provide a sound reference to the structural improvement of separating seedlings device in the rapeseed substrate block seedlings transplanter for modern mechanized agriculture. [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.)

BACKGROUND: With the development of industrialization, the problem of heavy metal pollution in soil frequently breaks out, which seriously endangers human health. The accurate detection of heavy metals in soil has important guiding significance for comprehensive and systematic understanding of the migration and transformation of heavy metals in soil environment and the proposed effective treatment methods. OBJECTIVES: Establish rapid, efficient, and green pre-treatment techniques and analytical methods to achieve accurate detection of heavy metals in large-scale on-site soil samples. METHODS: The high temperature electrothermal evaporating graphite furnace is used as the atomizer. After weighing, the sample is selectively evaporated by gradient heating, combined with two-channel heat transfer quartz tube, two-way argon online dilution, ICP-MS transient scanning, matrix matching external correction, etc. RESULTS: According to the experimental method, 20mg soil standard materials GBW07401, GBW07406, GBW07407, GBW07430 and GBW07456 were respectively weighed to establish an external calibration curve related to the element content and signal response in the sample. The linear correlation coefficient of the calibration curve of 7 elements in the sample was ≥ 0.999. Cr, Cu, Zn, As, Cd, Hg and Pb were determined in two field soil samples in Binjiang District of Hangzhou City. The method was RSD<7%, relative error <2.7%, detection limit was 1.2-32ng/g, recovery rate at 91% to 113%. CONCLUSIONS: Solid direct injection-electrothermal evaporation-mobile inductively coupled plasma mass spectrometry is a simple, fast, accurate and practical analytical technique that will play an important role in the rapid detection of heavy metals in soil at the environmental site. [ABSTRACT FROM AUTHOR]

The physical characteristics of rapeseed substrate block seedlings could affect its mechanical transplanting. In this paper, we measured the mechanical and biological characteristics of cubic rapeseed substrate block and link them to the safety in collecting, transporting and transplanting rapeseed substrate block seedlings. Orthogonal experiments were designed with substrate components ratio of earthworm dung, yellow brown soil, vermiculite mixture in the substrate at 1∶2∶1, 1∶1∶1 and 2∶1∶1 respectively, their associated compactness at 1.0, 1.2 and 1.4 respectively, and the concentration of boron and selenium in the solution at 0.24%, 0.27% and 0.30% respectively. We measured the mechanical characteristics of the rapeseed substrate block seeding (including its yield strength and drop loss rate) and the biological characteristics of the seedlings (including strong seedling index, substrate encapsulation degree and root robustness). The results showed that both substrate composition and compaction affected the mechanical characteristics of the rapeseed substrate block seedling, the seedling growth and root robustness at significant level or above; the concentration of boron and selenium also had a significant impact on the mechanical characteristic of the rapeseed substrate block seedlings. Substrate encapsulation degree and root robustness were both significantly affected by substrate composition ratio, compactness and concentration of the boron and selenium. The yield strength and drop loss rate of the rapeseed substrate block seedlings increased with both content and compactness of the yellow brown soil. With earthworm feces content increasing, the strong seedling index, substrate encapsulation degree and root robustness increased first followed by a decline. An increase in compaction degree and concentration of boron and selenium also resulted in an increase followed by decline in substrate encapsulation degree and root robustness. We used a comprehensive scoring method to determine the optimal combination of the seedling-raising factors by taking yield strength, strong seedling index, substrate encapsulation degree, root robustness and drop loss rate as evaluating factors with each having a weighting coefficient of 0.2. The results showed that the mechanical characteristics and the growth quality of the seedlings peaked when the ratio of all substrate components was 1∶1∶1, the compactness was 1.2 and the concentration of boron and selenium was 0.30%. A bench test results revealed that the requirements for mechanical transplanting were met when the transverse seedling pushing-speed was 20 mm/s, synchronous conveyor belt speed was 30 mm/s, the seedling picking frequency was 40 plants/min, the substrate loss rate was 2.57%, in which the feeding seedling successful rate was 90.93%. The failure of sending and collecting the seedlings could occur 1) in the process of mechanical transplanting where seedlings intertwined, resulting in an instability of the gravitational center of the seedlings, 2) in that the home-made transplanter might not be accurate enough in the bench test as there was a gap between the feeding tray and the synchronous conveyor belt, and that the installation angle of the row feeding device might bear errors. All these could result in the feeding-seedlings rate dropping to 90%. [ABSTRACT FROM AUTHOR]

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 Journal of Kunming Medical University / Kunming Yike Daxue Xuebao is the property of Kunming Medical Journal 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 China Petroleum Machinery is the property of China Petroleum Machinery 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 China Petroleum Machinery is the property of China Petroleum Machinery 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.)

Thrombelastography (TEG) is an image which can overall reflect the ability of coagulation, blood clotting and fibrinolysis dynamically. Changes of coagulation-anticoagulation system and fibrinolytic-antifibrinolytic system result in the hypercoagulable state in pregnant women. The hypercoagulable state is not only a kind of physiological protective mechanism, but also a high-risk factor for inducing coagulopathy. Once this dynamic balance is broken, obstetric complications will happen, which will do harm to maternal and fetal safety. TEG can reflect the coagulation state in pregnant women veritably and comprehensively. TEG has important value to predict the high-risk pregnancy such as recurrent spontaneous abortion, hypertensive disorders complicating pregnancy. Some peripartum complications, such as amniotic fluid embolism, postpartum hemorrhage and venous thrombus embolism can also be evaluated by TEG. It can also provide evidences for clinical decisions, early interventions, lessening or delaying of complications and preventing of adverse pregnant outcomes. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal 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 Shandong Medical Journal is the property of Shandong Medical Health Newspapers 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.)