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To evaluate the reliability of obtaining rock mechanics parameters and calculating the rock brittleness index using small core samples, the nanoindentation technology is applied to obtain mechanical parameters with the small-scale core samples or cuttings of 1 mm x 1 mm. Before nanoindentation testing, the mineral phase analysis is carried out. The scale is upgraded by the convolution method to obtain the micromechanical parameters. Compared with the mechanical experimental results of nanoindentation, the absolute error is less than 10%, which meets the needs of brittleness index calculation. The proposed method can obtain rock mechanical parameters using broken core samples or cuttings, providing a new technical method for obtaining experimental parameters for brittleness evaluation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences 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 present study aims at investigating the effect of temperature variation due to heat transfer between the formation and drilling fluids considering influx from the reservoir in the underbalanced drilling condition. Gas-liquid-solid three-phase flow model considering transient thermal interaction with the formation was applied to simulate wellbore fluid to calculate the wellbore temperature and pressure and analyze the influence of different parameters on fluid pressure and temperature distribution in annulus. The results show that the non-isothermal three-phase flow model with thermal consideration gives more accurate prediction of bottom-hole pressure (BHP) compared to other models considering geothermal temperature. Viscous dissipation, the heat produced by friction between the rotating drilling-string and well wall and drill bit drilling, and influx of oil and gas from reservoir have significant impact on the distribution of fluid temperature in the wellbore, which in turn affects the BHP. Bottom-hole fluid temperature decreases with increasing liquid flow rate, circulation time, and specific heat of liquid and gas but it increases with increasing in gas flow rate. It was found that BHP is strongly depended on the gas and liquid flow rates but it has weak dependence on the circulation time and specific heat of liquid and gas. BHP increase with increasing liquid flow rate and decreases with increasing gas flow rate.

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis 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.)

In order to investigate the environmental adaptation of Neosinocalamus affinis cuttings after transplantation, we used paraffin section technique to observe the anatomical structure of leaves, and the phenol-sulfuric acid method to determine the photosynthetic characteristics. The results revealed that with prolonged post-transplantation duration, the stomata of the cutting seedling leaves became smaller, although there were increases in stomatal density, leaf area and the thickness, cuticles, and upper and lower epidermis cells. Moreover, we observed an increase in the area of bulliform cells, which penetrated more deeply into the mesophyll, but the area of spindle cells was reduced. Furthermore, the net photosynthetic rate of leaves increased while the transpiration rate decreased. The contents of water and soluble sugars in leaves decreased, whereas the dry fresh weight ratio, the starch content, and the number of starch granules in leaves increased. We also noted a gradual accumulation of photosynthetic products in the leaves of cuttings with time following transplantation, which contributed to enhancing their environmental adaptation. Notably, the leaf structures and photosynthetic indices of cuttings observed at three months post-transplantation were similar to those characterizing 3-year-old seedlings. Therefore, reasonable protective measures should be taken during the first three months after transplantation using cuttings to prevent excessive water loss and enhance the survival of cuttings [ABSTRACT FROM AUTHOR]

Copyright of Journal of South China Normal University (Natural Science Edition) / Huanan Shifan Daxue Xuebao (Ziran Kexue Ban) is the property of Journal of South China Normal University (Natural Science Edition) 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.)

【Objective】The purpose of this study was to explore the effects on different cuttings treatments of rooting in roselle, which can provide reference for factory seedling cultivation and large-scale promotion and application of roselle.【Method】The cuttings in the upper, the middle and the lower segments of the main stem under the flowering period and the vegetative growth period of MG1501-1 and MG1502-2 were used as test materials. These materials treated with rooting agent and water(CK1-CK6) were planted in the river sand, nutritive soil∶fine loess substrate=1∶1 and field clay substrate. The effects of different cuttings rooting in roselle were evaluated based on the rooting time, the rooting number and callus induction.【Result】The rooting amount of cuttings of three different substrates was as follows: The river sand>nutritive soil+ fine loess substrate>field clay. For the cuttings of the flowering period, the number of roots was the most under the rooting agent treatments of MG1501-1 planted in the river sand substrate. The number of roots was up to 54.53. It was significantly higher than the field clay substrate(P<0.05,the same as below),increased by 130.57 % compared with the corresponding CK1,but no significant difference with nutritive soil+ fine loess substrate(P>0.05,the same below). For the cuttings of the vegetative growth period, the number of roots was the most under the rooting agent treatments of MG1501-1 planted in the river sand substrate. The number of roots was up to 44.14. It was significantly higher than the field clay substrate, but no significant difference with nutritive soil+fine loess substrate, and increased by 16.07 % compared with the corresponding CK3. On the third day of cutting, the highest rooting rate(93.34 %) and the lowest callus-generated rate(10.00 %) were found in the middle cuttings of the main stem of roselle, which were significantly higher than clay substrate and significantly lower than roselle respectively, and the root color was white.For the middle segment of the flowering period and the vegetative growth period, the number of roots was the most under the rooting agent treatments of MG1501-1 planted in river sand substrate after 14 days, the number of roots were respectively up to 22.88 and 22.61. They were respectively increased by 106.31 % compared with CK1 and increased by 25.42 % compared with CK3. They were respectively significantly higher than the upper cuttings of the same treatment and significantly higher than the upper and the lower cuttings of the same treatment.【Conclusion】Based on the above results, the best cuttage rooting mode of roselle MG1501-1 was selecting the plants in the vegetative growth period or the flowering period for picking, selecting the middle segment of softwood cuttings under the treatments of rooting agent 20 min and carrying out the cuttage rooting in the river sand substrate. [ABSTRACT FROM AUTHOR]

A lot of oil drilling wastes are produced during oil drilling work in Bohai offshore oilfield, which mainly contain waste oil drilling mud and waste oil drilling cuttings. The cost of environmental risks, transportation, treatment and disposal are increasing with the growth of development well of offshore oilfield. Therefore, the research of source reduction and resource disposal has been carried out. Negative pressure and micro-vibration filtration system was used to reduce the wastes on vibrating screen and simulation trial has been finished. The process “gel-breaking-centrifugation-ozone flotation-ceramic membrane” was used to treat the waste oil drilling mud and the treated drilling mud could be reused to prepare the fresh oil drilling fluid. The results showed that the waste drilling cuttings had a good dehydration effect, the liquid content of the waste oil drilling cuttings at outlet reached 21%-22%, and the oil content of clean water reused to prepare fresh oil drilling fluid was under 10 mg/L under the conditions that the liquid content was above 100% at inlet, the rotation rate was under 40% and mesh specifications were under API160. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Botanical Research is the property of Bulletin of Botanical Research 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 Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences 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 Natural Gas Industry is the property of Natural Gas Industry Journal Agency 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.)

More cuttings produced during gas drilling due to higher mechanical penetration rate and the cuttings usually tend to be larger in the bottom and smaller uniform in size when back to the wellhead. It is indicating that cuttings should appear successive breaking within the process of migration. According to particle collision broken theories, the successive breaking phenomenon was analyzed, and the calculating method of crash velocity for the occurrence of secondary breaking was given in this paper. Meanwhile, the breaking process matrix and the particle size distribution function were applied to study the re-cracking process of cuttings migration in the whole wellbore. The calculating results show that the cuttings in the wellbore were broken first in the form of the uneven size volumetric fracturing and then progressively turned into the surface fracture of the uniform process, and ultimately was tending towards stable particle size distribution state. [ABSTRACT FROM AUTHOR]