To investigate the distribution and velocity attributes of gas hydrates in the northern continental slope of South China Sea, Guangzhou Marine Geological Survey conducted four-component (4C) ocean-bottom seismometer...To investigate the distribution and velocity attributes of gas hydrates in the northern continental slope of South China Sea, Guangzhou Marine Geological Survey conducted four-component (4C) ocean-bottom seismometer (OBS) surveys. A case study is presented to show the results of acquiring and processing OBS data for detecting gas hydrates. Key processing steps such as repositioning, reorientation, PZ summation, and mirror imaging are discussed. Repositioning and reorientation find the correct location and direction of nodes. PZ summation matches P- and Z-components and sums them to separate upgoing and downgoing waves. Upgoing waves are used in conventional imaging, whereas downgoing waves are used in mirror imaging. Mirror imaging uses the energy of the receiver ghost reflection to improve the illumination of shallow structures, where gas hydrates and the associated bottom-simulating reflections (BSRs) are located. We developed a new method of velocity analysis using mirror imaging. The proposed method is based on velocity scanning and iterative prestack time migration. The final imaging results are promising. When combined with the derived velocity field, we can characterize the BSR and shallow structures; hence, we conclude that using 4C OBS can reveal the distribution and velocity attributes of gas hydrates.展开更多
Rice dwarf disease caused by rice dwarf virus (RDV) is one of the major rice virus diseases in China,which widely distributes in the rice area of China.A simple and rapid method for detection of RDV in rice plants a...Rice dwarf disease caused by rice dwarf virus (RDV) is one of the major rice virus diseases in China,which widely distributes in the rice area of China.A simple and rapid method for detection of RDV in rice plants and Nephotettix cincticeps was investigated in this study,and the whole detection only lasted for 20 min.After diseased leaves of rice (10 mg) and leaves of Nephotettix cincticeps (10 mg) both infected by RDV were ground by sterile water (100 μl),the supernatant was analyzed by 1% agarose gel electrophoresis to steadily detect five specific electrophoretic bands with 1 000 bp to 5 000 bp.However,there was no electrophoretic band in the healthy rice leaves and aqueous extract of non-viruliferous N.cincticeps.Therefore,this method was more rapid and simple to detect RDV in rice plants and Nephotettix cincticeps,which avoided expensive reagents and tedious steps of conventional serological testing and molecular detection (RT-PCR and Western-blot).展开更多
在我们生活中,与水有接触或者可能接触的电器产品,在国家标准中都对其有相应的防护要求。一般 IP 防护等级测试实际生产过程中经常要用水来测试,但是动力电池箱在线用水测试整机会造成后续的除水、清洁一些工作量加大,为此我们通过实验...在我们生活中,与水有接触或者可能接触的电器产品,在国家标准中都对其有相应的防护要求。一般 IP 防护等级测试实际生产过程中经常要用水来测试,但是动力电池箱在线用水测试整机会造成后续的除水、清洁一些工作量加大,为此我们通过实验换算对应 IP 等级的气密性测试参数关系,改变测试方法,引入直压式和差压式气密性测试仪进行产品防护等级检验。展开更多
[Objective] The experiment aimed to explore physiological and biochemical changes of leaves after plants were mutated. [Method] A rice double mutant with stripes on stems, leaves and spikelets were taken as experiment...[Objective] The experiment aimed to explore physiological and biochemical changes of leaves after plants were mutated. [Method] A rice double mutant with stripes on stems, leaves and spikelets were taken as experimental materials to study the enzyme activity changes in different growth stages and amino acid variation in rice. [ Result] The SOD activity in mutant was higher than that in wild plant at tillering metaphase, but lower than that in wild type before heading stage and late flowering; the POD activity in three stages increased firstly then declined and the activity showed highest maximal activity at before heading stage. However, the POD activity in wild type showed the opposite change trend; the CAT activity presented degression at three stages, especially high at tillering metaphase, but reverse changes in wild type; the MDA activity decreased at three stages, but it was still higher than that in wild type, besides, the soluble sugar content of mutant was lower, but total amino acid content was increased. [ Conclusion] The expression of mutant characteristics was correlated with SOD, POD, CAT and MDA activity Changes and these changes made the mutant survive and rice quality change at last.展开更多
[Objective] In order to better meet the requirement of crops on a more and more accurate water content under various planting environment of modern agri-culture, an automatic test system of soil water characteristic c...[Objective] In order to better meet the requirement of crops on a more and more accurate water content under various planting environment of modern agri-culture, an automatic test system of soil water characteristic curve was designed by combining the conceptions of soil moisture content and soil water potential. [Method] Electronic soil moisture tension meter was used to determine the real-time tension value of soil moisture in the tested container, and the electronic Weigh sensor was used to determine soil Weigh. Minusing method was used to calculate soil moisture content, based on which the soil water characteristic curve was plotted. [Result] Through the filed survey of 2 different kinds of soil in Jiangsu Province, the results were as fol ows: soil of different composition showed different trend in soil water characteristic curve that the soil water characteristic relation of the sandy soil in the old course of the Yel ow River in Xuzhou was Y=-0.000 2X3+0.027 7X2-1.644 5X+38.161, R2=0.991 9; while the soil water characteristic relation of the saline-alkali soil in Jinhai Farm of Dafeng was Y=-0.00 2X2-0.426X+39.905, R2=0.991 3. [Con-clusion] The automatic test system of soil water characteristic curve soil water char-acteristics curve could reflect soil moisture content and soil water potential, as wel as reflect the effectiveness of soil water to plant growth, providing basis for the sci-entific irrigation.展开更多
It’s very complicated to calculate and analyze the wave and current loads on naval architectures since the sea condition is uncertain and complicated and the determinants vary from different form types and dimensions...It’s very complicated to calculate and analyze the wave and current loads on naval architectures since the sea condition is uncertain and complicated and the determinants vary from different form types and dimensions. For calculating the wave and current loads on upright small-long-size pipe, the Morrison equation is practical and applied. Jacket platform is a kind of offshore space frame structure comprised of lots of poles that are circular cylinders with small diameter and in the oblique status relative to seabed. In this paper, based on Morrison equation, the specific method and procedure calculating the wave and current loads on launching jacket are given and applied on a typical launching jacket. The instance shows that the method and procedure are convenient and make the calculation and analysis in good agreement with actual launching.展开更多
Based on laboratory results of time-dependent mechanical behavior tests,we investigated short-term and mechanical creep behavior of sandstone,observed in conventional triaxial compression experiments at room temperatu...Based on laboratory results of time-dependent mechanical behavior tests,we investigated short-term and mechanical creep behavior of sandstone,observed in conventional triaxial compression experiments at room temperature,using a servo-controlled rheology testing machine.Given our short-term experimental test results,we confirmed deviatoric creep stress levels of sandstone.Multiple deviatoric stress levels were applied in steps to each sample.Each deviatoric stress level before the final failed deviatoric stress was maintained for 48 h or longer.Time-dependent variations of axial strains of sandstone samples are discussed and evaluated.During the creep tests,complete tertiary creep curves of sandstone were observed under failed deviatoric stress levels with different confining pressures.Slices of coal in sandstone samples can lead to distinct tertiary creep deformation failure.展开更多
AIM: To study the clinical significance of minimal ascites, which was only defined by the CT and whose nature was not determined preoperatively, in the relationship with the peritoneal carcinomatosis. METHODS: The m...AIM: To study the clinical significance of minimal ascites, which was only defined by the CT and whose nature was not determined preoperatively, in the relationship with the peritoneal carcinomatosis. METHODS: The medical records and the dynamic CT films of 118 patients with gastric cancer were reviewed. Factors associated with peritoneal carcinomatosis were analyzed in 40 patients who had CT-defined ascites of which the nature was surgically confirmed, RESULTS: Only 12.5-25% of the CT-defined minimal ascites, whose volume was estimated to be less than 50 mL, were associated with peritoneal carcinomatosis. When the estimated CT-defined ascitic volume was 50 mL or more, peritoneal carclnomatosis was identified in 75-100%. When CT-defined lymph node enlargements were not found beyond the regional gastric area, perigastric invasions were not suspected, and the size of tumor was less than 3 cm, peritoneal carcinomatosis seemed significantly less accompanied at the univariate analysis. However, except for the minimal volume of CT- defined ascites in comparison with the mild or more, other factors were not confirmed multivariately. CONCLUSION: In the patients with gastric cancer, CT- defined minimal ascites alone is rarely associated with peritoneal carcinomatosis, if it does not accompany other signs suggestive of malignant seeding. Therefore, consideration of active curative resection should not be hesitated, if CT-defined minimal ascites is the only delusive sign.展开更多
基金supported by the National Hi-tech Research and Development Program of China(863 Program)(Grant No.2013AA092501)the China Geological Survey Projects(Grant Nos.GZH201100303 and GZH201100305)
文摘To investigate the distribution and velocity attributes of gas hydrates in the northern continental slope of South China Sea, Guangzhou Marine Geological Survey conducted four-component (4C) ocean-bottom seismometer (OBS) surveys. A case study is presented to show the results of acquiring and processing OBS data for detecting gas hydrates. Key processing steps such as repositioning, reorientation, PZ summation, and mirror imaging are discussed. Repositioning and reorientation find the correct location and direction of nodes. PZ summation matches P- and Z-components and sums them to separate upgoing and downgoing waves. Upgoing waves are used in conventional imaging, whereas downgoing waves are used in mirror imaging. Mirror imaging uses the energy of the receiver ghost reflection to improve the illumination of shallow structures, where gas hydrates and the associated bottom-simulating reflections (BSRs) are located. We developed a new method of velocity analysis using mirror imaging. The proposed method is based on velocity scanning and iterative prestack time migration. The final imaging results are promising. When combined with the derived velocity field, we can characterize the BSR and shallow structures; hence, we conclude that using 4C OBS can reveal the distribution and velocity attributes of gas hydrates.
文摘Rice dwarf disease caused by rice dwarf virus (RDV) is one of the major rice virus diseases in China,which widely distributes in the rice area of China.A simple and rapid method for detection of RDV in rice plants and Nephotettix cincticeps was investigated in this study,and the whole detection only lasted for 20 min.After diseased leaves of rice (10 mg) and leaves of Nephotettix cincticeps (10 mg) both infected by RDV were ground by sterile water (100 μl),the supernatant was analyzed by 1% agarose gel electrophoresis to steadily detect five specific electrophoretic bands with 1 000 bp to 5 000 bp.However,there was no electrophoretic band in the healthy rice leaves and aqueous extract of non-viruliferous N.cincticeps.Therefore,this method was more rapid and simple to detect RDV in rice plants and Nephotettix cincticeps,which avoided expensive reagents and tedious steps of conventional serological testing and molecular detection (RT-PCR and Western-blot).
文摘在我们生活中,与水有接触或者可能接触的电器产品,在国家标准中都对其有相应的防护要求。一般 IP 防护等级测试实际生产过程中经常要用水来测试,但是动力电池箱在线用水测试整机会造成后续的除水、清洁一些工作量加大,为此我们通过实验换算对应 IP 等级的气密性测试参数关系,改变测试方法,引入直压式和差压式气密性测试仪进行产品防护等级检验。
基金Supported by Program for New Century Excellent Talents in University(NCET-04-0907)the Innovative Research Team in University (IRT0453)~~
文摘[Objective] The experiment aimed to explore physiological and biochemical changes of leaves after plants were mutated. [Method] A rice double mutant with stripes on stems, leaves and spikelets were taken as experimental materials to study the enzyme activity changes in different growth stages and amino acid variation in rice. [ Result] The SOD activity in mutant was higher than that in wild plant at tillering metaphase, but lower than that in wild type before heading stage and late flowering; the POD activity in three stages increased firstly then declined and the activity showed highest maximal activity at before heading stage. However, the POD activity in wild type showed the opposite change trend; the CAT activity presented degression at three stages, especially high at tillering metaphase, but reverse changes in wild type; the MDA activity decreased at three stages, but it was still higher than that in wild type, besides, the soluble sugar content of mutant was lower, but total amino acid content was increased. [ Conclusion] The expression of mutant characteristics was correlated with SOD, POD, CAT and MDA activity Changes and these changes made the mutant survive and rice quality change at last.
基金Supported by the Fund for Independent Innovation of Agricultural Sciences in Jiangsu Province(CX(13)3031)~~
文摘[Objective] In order to better meet the requirement of crops on a more and more accurate water content under various planting environment of modern agri-culture, an automatic test system of soil water characteristic curve was designed by combining the conceptions of soil moisture content and soil water potential. [Method] Electronic soil moisture tension meter was used to determine the real-time tension value of soil moisture in the tested container, and the electronic Weigh sensor was used to determine soil Weigh. Minusing method was used to calculate soil moisture content, based on which the soil water characteristic curve was plotted. [Result] Through the filed survey of 2 different kinds of soil in Jiangsu Province, the results were as fol ows: soil of different composition showed different trend in soil water characteristic curve that the soil water characteristic relation of the sandy soil in the old course of the Yel ow River in Xuzhou was Y=-0.000 2X3+0.027 7X2-1.644 5X+38.161, R2=0.991 9; while the soil water characteristic relation of the saline-alkali soil in Jinhai Farm of Dafeng was Y=-0.00 2X2-0.426X+39.905, R2=0.991 3. [Con-clusion] The automatic test system of soil water characteristic curve soil water char-acteristics curve could reflect soil moisture content and soil water potential, as wel as reflect the effectiveness of soil water to plant growth, providing basis for the sci-entific irrigation.
基金Supported by Item of Doctor Subject of Colleges and University (No.2000014125) and the Education Office of Liaoning Province (No.05l091).
文摘It’s very complicated to calculate and analyze the wave and current loads on naval architectures since the sea condition is uncertain and complicated and the determinants vary from different form types and dimensions. For calculating the wave and current loads on upright small-long-size pipe, the Morrison equation is practical and applied. Jacket platform is a kind of offshore space frame structure comprised of lots of poles that are circular cylinders with small diameter and in the oblique status relative to seabed. In this paper, based on Morrison equation, the specific method and procedure calculating the wave and current loads on launching jacket are given and applied on a typical launching jacket. The instance shows that the method and procedure are convenient and make the calculation and analysis in good agreement with actual launching.
基金Projects 50709008 and 50539110 are supported by the National Natural Science Foundation of China.
文摘Based on laboratory results of time-dependent mechanical behavior tests,we investigated short-term and mechanical creep behavior of sandstone,observed in conventional triaxial compression experiments at room temperature,using a servo-controlled rheology testing machine.Given our short-term experimental test results,we confirmed deviatoric creep stress levels of sandstone.Multiple deviatoric stress levels were applied in steps to each sample.Each deviatoric stress level before the final failed deviatoric stress was maintained for 48 h or longer.Time-dependent variations of axial strains of sandstone samples are discussed and evaluated.During the creep tests,complete tertiary creep curves of sandstone were observed under failed deviatoric stress levels with different confining pressures.Slices of coal in sandstone samples can lead to distinct tertiary creep deformation failure.
文摘AIM: To study the clinical significance of minimal ascites, which was only defined by the CT and whose nature was not determined preoperatively, in the relationship with the peritoneal carcinomatosis. METHODS: The medical records and the dynamic CT films of 118 patients with gastric cancer were reviewed. Factors associated with peritoneal carcinomatosis were analyzed in 40 patients who had CT-defined ascites of which the nature was surgically confirmed, RESULTS: Only 12.5-25% of the CT-defined minimal ascites, whose volume was estimated to be less than 50 mL, were associated with peritoneal carcinomatosis. When the estimated CT-defined ascitic volume was 50 mL or more, peritoneal carclnomatosis was identified in 75-100%. When CT-defined lymph node enlargements were not found beyond the regional gastric area, perigastric invasions were not suspected, and the size of tumor was less than 3 cm, peritoneal carcinomatosis seemed significantly less accompanied at the univariate analysis. However, except for the minimal volume of CT- defined ascites in comparison with the mild or more, other factors were not confirmed multivariately. CONCLUSION: In the patients with gastric cancer, CT- defined minimal ascites alone is rarely associated with peritoneal carcinomatosis, if it does not accompany other signs suggestive of malignant seeding. Therefore, consideration of active curative resection should not be hesitated, if CT-defined minimal ascites is the only delusive sign.