The effect of CO2 and NaCl on the initial stage of atmospheric corrosion of AZ91 magnesium alloy was studied. The observation of surface morphology by optical microscopy (OM), scanning electron microscopy (SEM) an...The effect of CO2 and NaCl on the initial stage of atmospheric corrosion of AZ91 magnesium alloy was studied. The observation of surface morphology by optical microscopy (OM), scanning electron microscopy (SEM) and the analysis of corrosion products by X-ray diffraction (XRD) were integrated to investigate corrosion evolution. The results showed that NaCl stimulated the corrosion by promoting the formation of thin electrolyte film, increasing the conductivity and breaking the protective film in the absence of CO2. The morphology of the corroded samples with deposited NaCl was more homogenous in the presence of CO2. It was suggested that NaCl-induced corrosion was inhibited in the presence of CO2 by the formation of slightly soluble corrosion products containing hydroxy carbonates and hydroxy chlorides that provided a partly protective layer on the surface of the magnesium alloy.展开更多
The formation and development of typhoons are closely related to the disturbed low vortexes at the planetary boundary layer(PBL). The effects of five PBL parameterization schemes(PBL schemes hereinafter) on the trajec...The formation and development of typhoons are closely related to the disturbed low vortexes at the planetary boundary layer(PBL). The effects of five PBL parameterization schemes(PBL schemes hereinafter) on the trajectory,intensity, and distribution of physical quantities are studied using the mesoscale WRF model on Super Typhoon Sanba(2012) during its initial stage. Results show that the five PBL schemes exhibit significant different effects on the simulated intensity and path. The results simulated by QNSE and ACM2 without the Bogus method are close to the best track data in the numerical experiments. When the Bogus method is adopted, the simulated trajectories improve significantly because the initial field is close to the true data. Among the five PBL schemes, QNSE and ACM2 with the Bogus method present improved simulated path and intensity compared with the three other schemes. This finding indicates that the two schemes deal with the initial PBL process satisfactorily, especially in the formation and development of disturbed low vortexes. The differences in the treatment methods of the five PBL schemes affect the surface layer physical quantities and the middle and upper atmospheres during the middle to late periods of the typhoon.Although QNSE and ACM2 present better simulation results than other schemes, they exhibit a few differences in the internal structure of the typhoon. The results simulated by MYJ are worse, and this method may be unsuitable for studying the formation and development of typhoons.展开更多
Four quarters' water collecting and monitoring samples were done in the mining subsidence lakes of different water storing periods ( 2 to 7 years), considering the water storing time and pollution sources state of ...Four quarters' water collecting and monitoring samples were done in the mining subsidence lakes of different water storing periods ( 2 to 7 years), considering the water storing time and pollution sources state of the subsidence lakes. The following indexes were discussed such as organic indexes (TOC, CODM,, BOD, COD), nutrient salts (TN, NH4^+, NO3, NO,, Kjeldahl Nitrogen, TP, PO4^3- ), etc. It is shown that water quality of the mining subsidence lake during the initial stage ( 2 years to 7 years) can stay relatively stable with a fluctuation during different quarters in a year, which can reach class Ill or IV of the Surthcc Water Environmental Quality Standard.展开更多
The initial stage of Ag film growth on Cu(100). Ta(100) and Ta(110) single crystals as well as YBaCuO on Si single crystal covered by Pd was investigated in situ by means of LAS 600 surface analysis system with a sput...The initial stage of Ag film growth on Cu(100). Ta(100) and Ta(110) single crystals as well as YBaCuO on Si single crystal covered by Pd was investigated in situ by means of LAS 600 surface analysis system with a sputtering source in sample preparation chamber. The results show that the initial state for Ag / Cu(100) film growth is typical S-K model, for Ag / Ta(100) and Ag / Ta(110)they have the same S-K characteristics, but due to the different surface energies of two crystalline planes. there is some difference for Ag / Ta (100) and Ag / Ta(110). YBCO sputterjng process is rather complex and Cu is the first element appearing in the film.展开更多
Sometimes, early star formation can be found in cold and dense molecular clouds, such as an infrared dark cloud. Considering that star formation often occurs in clusters, H II regions may be triggering a new generatio...Sometimes, early star formation can be found in cold and dense molecular clouds, such as an infrared dark cloud. Considering that star formation often occurs in clusters, H II regions may be triggering a new generation of star formation, so we can search for the initial stage of massive star formation around H II regions. Based on the above, this work introduces one method to search for the initial stage of massive star formation around H II regions. Towards one section of the H II region G18.2-0.3, multiwavelength observations are carried out to investigate its physical properties. Through analysis, we find three potential initial stages of massive star formation, suggesting that it is feasible to use in searching for the initial stage of massive star formation around H II regions.展开更多
Objective: To observe the therapeutic effect of Xiehuo Yangyin powder (XHYY) in treating the initial stage of toxic and diffuse goiter (Graves disease). Methods: Sixty patients were randomly divided into two groups, t...Objective: To observe the therapeutic effect of Xiehuo Yangyin powder (XHYY) in treating the initial stage of toxic and diffuse goiter (Graves disease). Methods: Sixty patients were randomly divided into two groups, the treated group (n = 30) was treated with XHYY and methimazole, while the control group (n = 30) was treated with methimazole alone. The TCM syndrome score and展开更多
In a bid to establish a strong scientific and technological (S&T) innovation base in China, the State S&T leading group, the top government organ for S&T issues, gave the go-ahead, on June 6,1998, for the ...In a bid to establish a strong scientific and technological (S&T) innovation base in China, the State S&T leading group, the top government organ for S&T issues, gave the go-ahead, on June 6,1998, for the Chinese Academy of Sciences (CAS) to introduce a pilot project for the national knowledge innovation program (KIP). The objective of the pilot project is to re-structure the Academy into three major bases:展开更多
The liberation of women is the historical process in which women have striven for gender equality, freedom from oppression, confinement and discrimination, and are becoming the masters of the society and their own des...The liberation of women is the historical process in which women have striven for gender equality, freedom from oppression, confinement and discrimination, and are becoming the masters of the society and their own destinies. According to the diversity in history and the state, the process can be divided into a serial of correlated phases, with each phase focusing on different issues. Sexism order in China had remained stable in the traditional society for centuries through a set of institutions. Women had believed in a sexual order and the rules of propriety, which advocated that men were superior to women. After the People’s Republic of China was founded in 1949, women’s rights in politics, economy, society, and even family were recognized and secured by the Constitution and laws just as men’s during a short period. Women’s liberation in China has made a significant progress.展开更多
Due to climate change, extreme heat stress events have become more frequent, adversely affecting rice yield and grain quality. The accumulation and translocation of dry matter and nitrogen substances are essential for...Due to climate change, extreme heat stress events have become more frequent, adversely affecting rice yield and grain quality. The accumulation and translocation of dry matter and nitrogen substances are essential for rice yield and grain quality. To assess the impact of high temperature stress(HTS) at the early panicle initiation(EPI) stage on the accumulation, transportation, and distribution of dry matter and nitrogen substances in various organs of rice, as well as the resulting effects on rice yield and grain quality, pot experiments were conducted using an indica rice cultivar Yangdao 6(YD6) and a japonica rice cultivar Jinxiangyu 1(JXY1) under both normal temperature(32 ℃/26 ℃) and high temperature(38 ℃/29 ℃) conditions. The results indicated that exposure to HTS at the EPI stage significantly decreased rice yield by reducing spikelet number per panicle, grain-filling rate, and grain weight. However, it improved the nutritional quality of rice grains by increasing protein and amylose contents. The reduction in nitrogen and dry matter accumulation accounted for the changes in spikelet number per panicle, grain-filling rate, and grain size. Under HTS, the decrease in nitrogen accumulation accompanied by the reduction in dry matter may be due to the down-regulation of leaf net photosynthesis and senescence, as evidenced by the decrease in nitrogen content. Furthermore, the decrease in sink size limited the translocation of dry matter and nitrogen substances to grains, which was closely related to the reduction in grain weight and the deterioration of grain quality. These findings significantly contribute to our understanding of the mechanisms of HTS on grain yield and quality formation from the perspective of dry matter and nitrogen accumulation and translocation. Further efforts are needed to improve the adaptability of rice varieties to climate change in the near future.展开更多
High temperatures cause physiological and biochemical changes and significantly affect young panicle development of rice(Oryza sativa L.).Brassinosteroids play important roles in enhancing crop stress resistance.In th...High temperatures cause physiological and biochemical changes and significantly affect young panicle development of rice(Oryza sativa L.).Brassinosteroids play important roles in enhancing crop stress resistance.In this study,we subjected rice cultivars Huanghuazhan(heat-resistant)and IR36(heat-sensitive)to high temperature(HT,40 oC)or normal temperature(NT,33 oC)for 7 d at the panicle initiation stage,in conjunction with application of 24-epibrassinolide[EBR,a synthetic brassinolide(BR)]or brassinazole(BRZ,a BR biosynthesis inhibitor)at the beginning of the treatments.HT exacerbated spikelet degeneration and inhibited young panicle growth,which were partially prevented by EBR application,while BRZ application aggravated the reduction in spikelet number.HT decreased the contents of BR,active cytokinins(aCTK),active gibberellins(aGA)and indole-3-acetic acid(IAA),but increased the content of abscisic acid(ABA)in young panicles.The activities of key enzymes involved in sucrose hydrolysis,glycolysis and the tricarboxylic acid cycle in young panicles were decreased with the change of endogenous hormone levels under HT.In addition,the contents of H2O2 and malondialdehyde(MDA)were increased and the activities of antioxidant enzymes were decreased in young panicles.Exogenous application of EBR induced the expression of phytohormone biosynthesis-related genes and down-regulated the expression of phytohormone catabolism-related genes to increase the contents of endogenous BR,aCTK,aGA and ABA,thus promoting the decomposition and utilization of sucrose in young panicles,enhancing the activities of superoxide dismutase,catalase and peroxidase,and reducing the accumulation of H2O2 and MDA in young panicles,whereas application of BRZ had the opposite physiological effects.These results showed that brassinosteroids mediate endogenous phytohormone metabolism to alleviate HT injury at the panicle initiation stage in rice.展开更多
There are abundant water power resources in the Yalong River which are suitable for the large hydroelectric engineering. But a reliability study should be made for the valley which liable to frequent earthquakes. The ...There are abundant water power resources in the Yalong River which are suitable for the large hydroelectric engineering. But a reliability study should be made for the valley which liable to frequent earthquakes. The color infrared aerophotos, multi-spectral photography and thermal infrared scanning had been specially done besides MSS image, processing. Researches on remote sensing applications to engineering geology, hydrogeology, deformation of neo-tectonics, Iandslide, mud-rock flow, ecological environment and geographical information system had been carried out by more than 20 research units.展开更多
The effects of SO_2 on the initial atmospheric corrosion of AZ91D magnesiumalloy were investigated in laboratory. Met-allographic observation, SEM (Scanning ElectronMicroscopy), XRD (X-ray Diffraction) and XPS (X-ray ...The effects of SO_2 on the initial atmospheric corrosion of AZ91D magnesiumalloy were investigated in laboratory. Met-allographic observation, SEM (Scanning ElectronMicroscopy), XRD (X-ray Diffraction) and XPS (X-ray Proton Spectrograph) were used to analyze anddiscuss the initial surface morphology of corrosion layers and corrosion products. The corrosionrate of the alloy increases with increasing the content of SO_2. The initial attack has thecharacteristics of localized corrosion and preferentially concentrates on a phase. MgO and Mg(OH)_2form at first, which provide a protective layer, then the existence of SO_2 decreases the pH of thethin solution on the alloy, accelerates dissolution process, and promotes the formation of MgSO_3centre dot 6H_2O and MgSO_4 centre dot 6H_2O, meanwhile cracks were found on the corrosion productswith corrosion continuation. These soluble corrosion products and the cracks provide the paths forfiltering oxygen and corrosion pollutants into the matrix, which results in severe localizedcorrosion and the loss of protective function of film.展开更多
Background: The management of the rectal cancer requires accurate initial staging. Besides routinely performed conventional imaging, during the last decade 18F-FDG PET/CT became a popular whole-body metabolic imaging...Background: The management of the rectal cancer requires accurate initial staging. Besides routinely performed conventional imaging, during the last decade 18F-FDG PET/CT became a popular whole-body metabolic imaging for preoperative TNM classification. The purpose of the study was to evaluate the role of 18F-FDG PET/CT in the rectal cancer staging. Patients and methods: 45 patients with rectal cancer who preoperatively underwent 18F-FDG PET/CT imaging in the period from 2011 to 2014 were analyzed. All patients were referred to the surgery afterwards. Histopathologic findings were used as a standard of reference. Descriptive techniques were used for frequency analyses and sensitivity calculations. The X2 test was used for significance calculation of the contingency tables while Monte Carlo simulation and Fisher's exact test were used for the table fields where number of cases was smaller than demanded. Results: The average SUVmax value of the primary tumor for all T stages was 26.02 gm/mL. The average SUVmax values of the lymph nodes in N1 stage and N2 stage were 6.04 gm/mL and 6.33 gm/mL, respectively. PET/CT detected benign lesions in 17 (28.3%) patients with average SUVmax of 15.4 mg/mL. The vaginal wall infiltration was detected in 2 (4.4%) patients. Penetration of mesorectal fascia was detected in 21 (46.7%) of patients. Four patients (8.9%) had liver metastases identified by lSF-FDG PET/CT. The overall sensitivity, specificity and accuracy of 18F-FDG PET/CT in T staging was 90.7%, 91.9%, and 90.5%, respectively. The overall sensitivity, specificity and accuracy of 18F-FDG PET/CT in detection of metastatic lymph node was 85.8%, 89.8%, and 89%, respectively. PET/CT shows low sensitivity (77.3%) and specificity (25%) in analyzing mesorectal fascia involvement. The overall sensitivity of 18F-FDG PET/CT in M staging was 100%. Conclusions: 18F-FDG PET/CT is highly sensitive for initial T staging of rectal cancer especially in advanced disease. This imaging modality is highly accurate in detection of metastatic lymph nodes and liver metastases, but it has no role in defining ofmesorectal fascia involvement. Therefore, 18F-FDG PET/CT should be incorporated routinely in preoperative staging together with conventional imaging.展开更多
This study aimed to investigate the combined effects of nitrogen level (high and ordinary) and high temperature stress (37 ℃, 4 d) at the late panicle ini- tiation stage on yield, SPAD value and soluble sugar con...This study aimed to investigate the combined effects of nitrogen level (high and ordinary) and high temperature stress (37 ℃, 4 d) at the late panicle ini- tiation stage on yield, SPAD value and soluble sugar content of Ganxin 203, an early rice cultivar. The results showed that under both high and ordinary nitrogen levels, high temperature stress reduced the seed-setting rate, yield per stem, SPAD value and soluble sugar content of Ganxin 203; under both high and ordinary tem- peratures, high nitrogen level increased the seed-setting rate, yield per stem and soluble sugar content of Ganxin 203; the seed-setting rate, yield per stem and yield per plant of Ganxin 203 under high temperature and high nitrogen level were higher than those under high temperature and ordinary nitrogen level. It suggests that ap- propriate high nitrogen level contributes to weakening the negative effects of high temperature stress on rice yield.展开更多
With validamycin A.(0.2 billion spores/ml) Paenibacillus polymyxa DN-1 3% AS as the test agent, the effects of different dosage and different application time on the control efficacy for' rich sheath blight were in...With validamycin A.(0.2 billion spores/ml) Paenibacillus polymyxa DN-1 3% AS as the test agent, the effects of different dosage and different application time on the control efficacy for' rich sheath blight were investigated. The results of two- year test showed that when the application amount was in the range of 45-90 g.a.i/ hm^2, the field efficacy of validamycin A-(0.2 billion spores/ml) P. polymyxa DN-1 3% AS in the initial infection stage of rich sheath blight (Le., the diseased plant rate was below 5%) reached 80.38%-89.06%, and that in the peak infection stage (i.e., the diseased plant rate was higher than 10%) reached only 41.12%-53.26%. The field efficacy of validamycin A.(0.2 billion spores/ml) P. polymyxa DN-1 3% AS at the early onset of rich sheath blight was significantly better than that at the onset, so that the application time of validamycin A .(0.2 billion spores/ml) P. polymyxa DN-1 3% AS should be appropriately brought forward in the prevention and control of rice sheath blight.展开更多
The nuisance from odor caused by municipal solid waste(MSW) is resulting in a growing number of public complaints and concerns. Odor pollution occurs in the initial decomposition stage of MSW, including waste collecti...The nuisance from odor caused by municipal solid waste(MSW) is resulting in a growing number of public complaints and concerns. Odor pollution occurs in the initial decomposition stage of MSW, including waste collection, transportation and early pre-treatment. Furthermore, decomposition takes place in waste facilities that are often close to living areas, which can result in odor impacts on local inhabitants. However, this aspect of odor impact from MSW has not been well studied. In the current study, lab-scale waste cells were designed to simulate MSW storage conditions in the early stage. The characteristics of VOCs emissions with different waste compositions were analyzed. The odor concentration( CO, non-dimensional) method and odor intensity were used for the assessment of odor. Ethanol was the substance with highest emission rate. The release rate of VOCs increased with the growth easily biodegradable waste(EBW). VOCs emissions was reduced by 25% when the proportion of EBW decreased from 60% to 45%. Methyl sulfide, ethanol, dimethyl disulfide and ethyl acetate were identified as typical odorants. The EBW proportion in waste is the main factor significantly influencing odor pollution. The CO was 244.51 for the 60% EBW condition, which was only 61.46 for 15% EBW condition. These study results provide important information for the implementation of a garbage sorting policy and the monitoring of odor pollution from waste management.展开更多
The present paper attempts to solve equations in the initial stage and the two-phase flow regime of fuel spray penetration using the HPM-Padétechnique,which is a combination of the homotopy perturbation method(HP...The present paper attempts to solve equations in the initial stage and the two-phase flow regime of fuel spray penetration using the HPM-Padétechnique,which is a combination of the homotopy perturbation method(HPM)and Padéapproximation.At the initial stage,the effects of the droplet drag and the air entrainment were explained while in the two-phase flow stage,the spray droplets had the same velocities as the entrained air.The results for various injection pressures and ambient densities are presented graphically and then discussed upon.The obtained results for these two stages show a good agreement with previously obtained expressions via successive approximations in the available literature.The numerical result indicates that the proposed method is straight forward to implement,efficient and accurate for solving nonlinear equations of fuel spray.展开更多
基金This work was financially supported by the Major State Basic Research Development Program of China (973 Program No. 19990650) and the Materials Science and Engineering Research Center Project of Jiangxi Province of China (No. ZX200401015)
文摘The effect of CO2 and NaCl on the initial stage of atmospheric corrosion of AZ91 magnesium alloy was studied. The observation of surface morphology by optical microscopy (OM), scanning electron microscopy (SEM) and the analysis of corrosion products by X-ray diffraction (XRD) were integrated to investigate corrosion evolution. The results showed that NaCl stimulated the corrosion by promoting the formation of thin electrolyte film, increasing the conductivity and breaking the protective film in the absence of CO2. The morphology of the corroded samples with deposited NaCl was more homogenous in the presence of CO2. It was suggested that NaCl-induced corrosion was inhibited in the presence of CO2 by the formation of slightly soluble corrosion products containing hydroxy carbonates and hydroxy chlorides that provided a partly protective layer on the surface of the magnesium alloy.
基金National Natural Science Foundation of China(41375033,41225018)National Basic Research Program of China(973 Program)(2013CB430100)Fundamental Research Funds for Central Universities of Lanzhou University(LZUJBKY-2013-K16)
文摘The formation and development of typhoons are closely related to the disturbed low vortexes at the planetary boundary layer(PBL). The effects of five PBL parameterization schemes(PBL schemes hereinafter) on the trajectory,intensity, and distribution of physical quantities are studied using the mesoscale WRF model on Super Typhoon Sanba(2012) during its initial stage. Results show that the five PBL schemes exhibit significant different effects on the simulated intensity and path. The results simulated by QNSE and ACM2 without the Bogus method are close to the best track data in the numerical experiments. When the Bogus method is adopted, the simulated trajectories improve significantly because the initial field is close to the true data. Among the five PBL schemes, QNSE and ACM2 with the Bogus method present improved simulated path and intensity compared with the three other schemes. This finding indicates that the two schemes deal with the initial PBL process satisfactorily, especially in the formation and development of disturbed low vortexes. The differences in the treatment methods of the five PBL schemes affect the surface layer physical quantities and the middle and upper atmospheres during the middle to late periods of the typhoon.Although QNSE and ACM2 present better simulation results than other schemes, they exhibit a few differences in the internal structure of the typhoon. The results simulated by MYJ are worse, and this method may be unsuitable for studying the formation and development of typhoons.
文摘Four quarters' water collecting and monitoring samples were done in the mining subsidence lakes of different water storing periods ( 2 to 7 years), considering the water storing time and pollution sources state of the subsidence lakes. The following indexes were discussed such as organic indexes (TOC, CODM,, BOD, COD), nutrient salts (TN, NH4^+, NO3, NO,, Kjeldahl Nitrogen, TP, PO4^3- ), etc. It is shown that water quality of the mining subsidence lake during the initial stage ( 2 years to 7 years) can stay relatively stable with a fluctuation during different quarters in a year, which can reach class Ill or IV of the Surthcc Water Environmental Quality Standard.
文摘The initial stage of Ag film growth on Cu(100). Ta(100) and Ta(110) single crystals as well as YBaCuO on Si single crystal covered by Pd was investigated in situ by means of LAS 600 surface analysis system with a sputtering source in sample preparation chamber. The results show that the initial state for Ag / Cu(100) film growth is typical S-K model, for Ag / Ta(100) and Ag / Ta(110)they have the same S-K characteristics, but due to the different surface energies of two crystalline planes. there is some difference for Ag / Ta (100) and Ag / Ta(110). YBCO sputterjng process is rather complex and Cu is the first element appearing in the film.
基金C.-P.Zhang is supported by the Young Researcher Grant of National Astronomical Observatories,Chinese Academy of Sciencespartly supported by the National Key Basic Research Program of China(973 Program) 2015CB857100+2 种基金the National Natural Science Foundation of China 11503035,11363004 and 11403042The GRS is a joint project of Boston University and Five College Radio Astronomy Observatoryfunded by the National Science Foundation under grants AST9800334,AST-0098562 and AST-0100793
文摘Sometimes, early star formation can be found in cold and dense molecular clouds, such as an infrared dark cloud. Considering that star formation often occurs in clusters, H II regions may be triggering a new generation of star formation, so we can search for the initial stage of massive star formation around H II regions. Based on the above, this work introduces one method to search for the initial stage of massive star formation around H II regions. Towards one section of the H II region G18.2-0.3, multiwavelength observations are carried out to investigate its physical properties. Through analysis, we find three potential initial stages of massive star formation, suggesting that it is feasible to use in searching for the initial stage of massive star formation around H II regions.
文摘Objective: To observe the therapeutic effect of Xiehuo Yangyin powder (XHYY) in treating the initial stage of toxic and diffuse goiter (Graves disease). Methods: Sixty patients were randomly divided into two groups, the treated group (n = 30) was treated with XHYY and methimazole, while the control group (n = 30) was treated with methimazole alone. The TCM syndrome score and
文摘In a bid to establish a strong scientific and technological (S&T) innovation base in China, the State S&T leading group, the top government organ for S&T issues, gave the go-ahead, on June 6,1998, for the Chinese Academy of Sciences (CAS) to introduce a pilot project for the national knowledge innovation program (KIP). The objective of the pilot project is to re-structure the Academy into three major bases:
文摘The liberation of women is the historical process in which women have striven for gender equality, freedom from oppression, confinement and discrimination, and are becoming the masters of the society and their own destinies. According to the diversity in history and the state, the process can be divided into a serial of correlated phases, with each phase focusing on different issues. Sexism order in China had remained stable in the traditional society for centuries through a set of institutions. Women had believed in a sexual order and the rules of propriety, which advocated that men were superior to women. After the People’s Republic of China was founded in 1949, women’s rights in politics, economy, society, and even family were recognized and secured by the Constitution and laws just as men’s during a short period. Women’s liberation in China has made a significant progress.
基金supported by the Jiangsu Agriculture Science and Technology Innovation Fund,China(Grant No.CX(23)1035)the National Natural Science Foundation of China(Grant Nos.32201888,32071943,and 32272197)+2 种基金the Provincial Natural Science Foundation of Jiangsu,China(Grant No.BK20200923)the National Key Research and Development Program of China(Grant Nos.SQ 2022YFD1500402 and SQ2022YFD2300304)the Priority Academic Program Development of Jiangsu Higher Education Institutions,China.
文摘Due to climate change, extreme heat stress events have become more frequent, adversely affecting rice yield and grain quality. The accumulation and translocation of dry matter and nitrogen substances are essential for rice yield and grain quality. To assess the impact of high temperature stress(HTS) at the early panicle initiation(EPI) stage on the accumulation, transportation, and distribution of dry matter and nitrogen substances in various organs of rice, as well as the resulting effects on rice yield and grain quality, pot experiments were conducted using an indica rice cultivar Yangdao 6(YD6) and a japonica rice cultivar Jinxiangyu 1(JXY1) under both normal temperature(32 ℃/26 ℃) and high temperature(38 ℃/29 ℃) conditions. The results indicated that exposure to HTS at the EPI stage significantly decreased rice yield by reducing spikelet number per panicle, grain-filling rate, and grain weight. However, it improved the nutritional quality of rice grains by increasing protein and amylose contents. The reduction in nitrogen and dry matter accumulation accounted for the changes in spikelet number per panicle, grain-filling rate, and grain size. Under HTS, the decrease in nitrogen accumulation accompanied by the reduction in dry matter may be due to the down-regulation of leaf net photosynthesis and senescence, as evidenced by the decrease in nitrogen content. Furthermore, the decrease in sink size limited the translocation of dry matter and nitrogen substances to grains, which was closely related to the reduction in grain weight and the deterioration of grain quality. These findings significantly contribute to our understanding of the mechanisms of HTS on grain yield and quality formation from the perspective of dry matter and nitrogen accumulation and translocation. Further efforts are needed to improve the adaptability of rice varieties to climate change in the near future.
基金funded by the Natural Science Foundation of Zhejiang Province,China(Grant No.LQ20C130009)the Science and Technology Project of Zhejiang Province,China(Grant No.2022C02034)the Special Fund for China Agricultural Research System(Grant No.CARS-01-22)。
文摘High temperatures cause physiological and biochemical changes and significantly affect young panicle development of rice(Oryza sativa L.).Brassinosteroids play important roles in enhancing crop stress resistance.In this study,we subjected rice cultivars Huanghuazhan(heat-resistant)and IR36(heat-sensitive)to high temperature(HT,40 oC)or normal temperature(NT,33 oC)for 7 d at the panicle initiation stage,in conjunction with application of 24-epibrassinolide[EBR,a synthetic brassinolide(BR)]or brassinazole(BRZ,a BR biosynthesis inhibitor)at the beginning of the treatments.HT exacerbated spikelet degeneration and inhibited young panicle growth,which were partially prevented by EBR application,while BRZ application aggravated the reduction in spikelet number.HT decreased the contents of BR,active cytokinins(aCTK),active gibberellins(aGA)and indole-3-acetic acid(IAA),but increased the content of abscisic acid(ABA)in young panicles.The activities of key enzymes involved in sucrose hydrolysis,glycolysis and the tricarboxylic acid cycle in young panicles were decreased with the change of endogenous hormone levels under HT.In addition,the contents of H2O2 and malondialdehyde(MDA)were increased and the activities of antioxidant enzymes were decreased in young panicles.Exogenous application of EBR induced the expression of phytohormone biosynthesis-related genes and down-regulated the expression of phytohormone catabolism-related genes to increase the contents of endogenous BR,aCTK,aGA and ABA,thus promoting the decomposition and utilization of sucrose in young panicles,enhancing the activities of superoxide dismutase,catalase and peroxidase,and reducing the accumulation of H2O2 and MDA in young panicles,whereas application of BRZ had the opposite physiological effects.These results showed that brassinosteroids mediate endogenous phytohormone metabolism to alleviate HT injury at the panicle initiation stage in rice.
文摘There are abundant water power resources in the Yalong River which are suitable for the large hydroelectric engineering. But a reliability study should be made for the valley which liable to frequent earthquakes. The color infrared aerophotos, multi-spectral photography and thermal infrared scanning had been specially done besides MSS image, processing. Researches on remote sensing applications to engineering geology, hydrogeology, deformation of neo-tectonics, Iandslide, mud-rock flow, ecological environment and geographical information system had been carried out by more than 20 research units.
基金This work was financially supported by the National Natural Science Foundation of China (No. 50171011 )the 973 Science Foundation of China (No. 19990650).
文摘The effects of SO_2 on the initial atmospheric corrosion of AZ91D magnesiumalloy were investigated in laboratory. Met-allographic observation, SEM (Scanning ElectronMicroscopy), XRD (X-ray Diffraction) and XPS (X-ray Proton Spectrograph) were used to analyze anddiscuss the initial surface morphology of corrosion layers and corrosion products. The corrosionrate of the alloy increases with increasing the content of SO_2. The initial attack has thecharacteristics of localized corrosion and preferentially concentrates on a phase. MgO and Mg(OH)_2form at first, which provide a protective layer, then the existence of SO_2 decreases the pH of thethin solution on the alloy, accelerates dissolution process, and promotes the formation of MgSO_3centre dot 6H_2O and MgSO_4 centre dot 6H_2O, meanwhile cracks were found on the corrosion productswith corrosion continuation. These soluble corrosion products and the cracks provide the paths forfiltering oxygen and corrosion pollutants into the matrix, which results in severe localizedcorrosion and the loss of protective function of film.
文摘Background: The management of the rectal cancer requires accurate initial staging. Besides routinely performed conventional imaging, during the last decade 18F-FDG PET/CT became a popular whole-body metabolic imaging for preoperative TNM classification. The purpose of the study was to evaluate the role of 18F-FDG PET/CT in the rectal cancer staging. Patients and methods: 45 patients with rectal cancer who preoperatively underwent 18F-FDG PET/CT imaging in the period from 2011 to 2014 were analyzed. All patients were referred to the surgery afterwards. Histopathologic findings were used as a standard of reference. Descriptive techniques were used for frequency analyses and sensitivity calculations. The X2 test was used for significance calculation of the contingency tables while Monte Carlo simulation and Fisher's exact test were used for the table fields where number of cases was smaller than demanded. Results: The average SUVmax value of the primary tumor for all T stages was 26.02 gm/mL. The average SUVmax values of the lymph nodes in N1 stage and N2 stage were 6.04 gm/mL and 6.33 gm/mL, respectively. PET/CT detected benign lesions in 17 (28.3%) patients with average SUVmax of 15.4 mg/mL. The vaginal wall infiltration was detected in 2 (4.4%) patients. Penetration of mesorectal fascia was detected in 21 (46.7%) of patients. Four patients (8.9%) had liver metastases identified by lSF-FDG PET/CT. The overall sensitivity, specificity and accuracy of 18F-FDG PET/CT in T staging was 90.7%, 91.9%, and 90.5%, respectively. The overall sensitivity, specificity and accuracy of 18F-FDG PET/CT in detection of metastatic lymph node was 85.8%, 89.8%, and 89%, respectively. PET/CT shows low sensitivity (77.3%) and specificity (25%) in analyzing mesorectal fascia involvement. The overall sensitivity of 18F-FDG PET/CT in M staging was 100%. Conclusions: 18F-FDG PET/CT is highly sensitive for initial T staging of rectal cancer especially in advanced disease. This imaging modality is highly accurate in detection of metastatic lymph nodes and liver metastases, but it has no role in defining ofmesorectal fascia involvement. Therefore, 18F-FDG PET/CT should be incorporated routinely in preoperative staging together with conventional imaging.
基金Supported by Special Scientific Research Fund of Meteorological Public Welfare Profession of China(GYHY201406025GYHY201006025)+2 种基金Special Fund for Agroscientific Research in the Public Interest of China(201403002)Young Talent Project of China Meteorological AdministrationJiangxi"555"Ganpo Yingcai Project~~
文摘This study aimed to investigate the combined effects of nitrogen level (high and ordinary) and high temperature stress (37 ℃, 4 d) at the late panicle ini- tiation stage on yield, SPAD value and soluble sugar content of Ganxin 203, an early rice cultivar. The results showed that under both high and ordinary nitrogen levels, high temperature stress reduced the seed-setting rate, yield per stem, SPAD value and soluble sugar content of Ganxin 203; under both high and ordinary tem- peratures, high nitrogen level increased the seed-setting rate, yield per stem and soluble sugar content of Ganxin 203; the seed-setting rate, yield per stem and yield per plant of Ganxin 203 under high temperature and high nitrogen level were higher than those under high temperature and ordinary nitrogen level. It suggests that ap- propriate high nitrogen level contributes to weakening the negative effects of high temperature stress on rice yield.
基金Supported by National Agricultural Science and Technology Achievement Transformation Fund of China(2010GB2C300196)Modern Agricultural Production Development Fund(Rice Industry)Project of Anhui Academy of Agricultural SciencesIntegration and Demonstration of Chemical Fertilizer and Agrochemical Reduction and Efficiency Increasing Technology for Rice in Rice-wheat(rape)Rotation Areas in Anhui(2016YFD0200806)~~
文摘With validamycin A.(0.2 billion spores/ml) Paenibacillus polymyxa DN-1 3% AS as the test agent, the effects of different dosage and different application time on the control efficacy for' rich sheath blight were investigated. The results of two- year test showed that when the application amount was in the range of 45-90 g.a.i/ hm^2, the field efficacy of validamycin A-(0.2 billion spores/ml) P. polymyxa DN-1 3% AS in the initial infection stage of rich sheath blight (Le., the diseased plant rate was below 5%) reached 80.38%-89.06%, and that in the peak infection stage (i.e., the diseased plant rate was higher than 10%) reached only 41.12%-53.26%. The field efficacy of validamycin A.(0.2 billion spores/ml) P. polymyxa DN-1 3% AS at the early onset of rich sheath blight was significantly better than that at the onset, so that the application time of validamycin A .(0.2 billion spores/ml) P. polymyxa DN-1 3% AS should be appropriately brought forward in the prevention and control of rice sheath blight.
基金financially supported by the Nation Natural Science Foundation of China (No. 51808520)the State Environmental Protection Key Laboratory of Odor Pollution Control (No. 20200502)。
文摘The nuisance from odor caused by municipal solid waste(MSW) is resulting in a growing number of public complaints and concerns. Odor pollution occurs in the initial decomposition stage of MSW, including waste collection, transportation and early pre-treatment. Furthermore, decomposition takes place in waste facilities that are often close to living areas, which can result in odor impacts on local inhabitants. However, this aspect of odor impact from MSW has not been well studied. In the current study, lab-scale waste cells were designed to simulate MSW storage conditions in the early stage. The characteristics of VOCs emissions with different waste compositions were analyzed. The odor concentration( CO, non-dimensional) method and odor intensity were used for the assessment of odor. Ethanol was the substance with highest emission rate. The release rate of VOCs increased with the growth easily biodegradable waste(EBW). VOCs emissions was reduced by 25% when the proportion of EBW decreased from 60% to 45%. Methyl sulfide, ethanol, dimethyl disulfide and ethyl acetate were identified as typical odorants. The EBW proportion in waste is the main factor significantly influencing odor pollution. The CO was 244.51 for the 60% EBW condition, which was only 61.46 for 15% EBW condition. These study results provide important information for the implementation of a garbage sorting policy and the monitoring of odor pollution from waste management.
文摘The present paper attempts to solve equations in the initial stage and the two-phase flow regime of fuel spray penetration using the HPM-Padétechnique,which is a combination of the homotopy perturbation method(HPM)and Padéapproximation.At the initial stage,the effects of the droplet drag and the air entrainment were explained while in the two-phase flow stage,the spray droplets had the same velocities as the entrained air.The results for various injection pressures and ambient densities are presented graphically and then discussed upon.The obtained results for these two stages show a good agreement with previously obtained expressions via successive approximations in the available literature.The numerical result indicates that the proposed method is straight forward to implement,efficient and accurate for solving nonlinear equations of fuel spray.