At the policy briefing held by the State Council Information Office on October 31,Guo Huanxin,Director-General of the Department of Metrology,State Administration for Market Regulation(SAMR),said that the overall conv...At the policy briefing held by the State Council Information Office on October 31,Guo Huanxin,Director-General of the Department of Metrology,State Administration for Market Regulation(SAMR),said that the overall conversion rate of international standards into China’s national standards has reached 86%by the end of September 2025,achieving the goal set in the National Standardization Development Outline,and providing sound support for green and low-carbon development.展开更多
The conversion rates of SO2 to SO42- and NO2 to HNO3+NO3- are estimated from the field-data obtained in Beijing in summer, 1988. The results show that the conversion rate of NO2 is about four times as much as that of ...The conversion rates of SO2 to SO42- and NO2 to HNO3+NO3- are estimated from the field-data obtained in Beijing in summer, 1988. The results show that the conversion rate of NO2 is about four times as much as that of SO2; The conversion rates have a diurnal variation in a day. On the average, the rate of SO2 is estimated to be 4.7% h-1 during the daytime and 3.4% h-1 during the nighttime. Similarly, the rate of NO2 is estimated to be 17.2% h-1 and 12% h-1 respectively.展开更多
Surface OH radical concentration in Beijing City was measured by impregnated filter trapping technique-high performance liquid chromatography (IFT-HPLC). The observed concentration of OH radical showed obvious diurnal...Surface OH radical concentration in Beijing City was measured by impregnated filter trapping technique-high performance liquid chromatography (IFT-HPLC). The observed concentration of OH radical showed obvious diurnal and seasonal variations, with maximum readings at noon or afternoon, similar to 80x10(6)OH/cm(3) in summer and similar to 20x10(6)-40x10(6)OH/cm(3) in fall. On the basis of measured data, the reaction rates related to the photochemical process of HO(x) (OH+HO(2)) were derived and characteristics of atmospheric chemical processes in the city were analyzed. The results showed that conversion rates of atmospheric OH and HO(2) in the summer of Beijing City were about 700x10(6) molecule/(cm(3) . s) and 600x10(6)molecule/(cm(3) . s), respectively. And the net production of OH in the air of the city mainly originated from the photolysis of the gaseous HNO(2), and the main sink of OH were the photochemical reactions with VOCs, NO(2), HCHO and CO. It was different from the clean area.展开更多
This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for wheat by data mining method based on data of"3414 fertilizer field trials"of whea...This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for wheat by data mining method based on data of"3414 fertilizer field trials"of wheat by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of wheat for plot was that,Y N≈a+b×optimum nitrogen application amount+c×optimum fertilizer amount of K+d×rainfall in growth season,Y P≈a+b×optimum fertilizer amount of K+c×rainfall in growth season,Y K≈a+b×temperature in growth season+c×rainfall in growth season-d×optimum yield-e×optimum nitrogen application amount,respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships.No significant relationships:13,of which 8 were soil nutrients,the results showed that soil nutrients had little effect on nutrient conversion rate and fertilizer utilization ratio;consistent significant relationships:4,they were all nitrogen and phosphorus,explaining the importance of nitrogen and phosphorus;contrary significant relationships:6,they were all nitrogen and phosphorus,illustrating that phosphorus and nitrogen had inhibitory effect;complementary significant relationships:31,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the measuring index of fertilizer efficiency in one season,while the nutrient conversion rate was the measuring index of fertilizer efficiency in more seasons.It showed that the fertilizer utilization rate was significantly correlated,or the nutrient conversion rate was significantly correlated.展开更多
This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for rice by data mining method based on data of"3414 fertilizer field trials"of rice ...This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for rice by data mining method based on data of"3414 fertilizer field trials"of rice by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of rice for plot was that,Y N≈a+b×optimum yield+c×optimum fertilizer amount of K,Y P≈a+b×optimum yield,Y K≈a respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships:①no significant relationships:25,of which 14 were soil nutrients and 9 were environmental factors,the results showed that soil nutrients and environmental factors had little effect on nutrient yield ratio and fertilizer utilization ratio;②consistent significant relationships:2,one was that yield ratio and utilization ratio of N were positively correlated with the optimum production,explaining the importance of N for production,the other was that yield ratio and utilization ratio of P had a significantly positive correlation with conversion rate and utilization ratio of N,illustrating that nitrogen and phosphorus had mutual promotion;③contrary significant relationships:5,these showed as negative correlations of fertilizer utilization ratio and positive correlation of nutrient conversion ratio;④complementary significant relationships:22,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the index of fertilizer efficiency in one season,while the nutrient conversion rate was the index of fertilizer efficiency in more seasons,which showed that the fertilizer utilization rate was significantly correlated,or the nutrient conversion rate was significantly correlated.展开更多
This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for maize by data mining method based on data of"3414 fertilizer field trials"of maiz...This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of maize for plot was that,Y N≈a+b×optimum yield,Y P≈a+b×optimum yield-c×optimum nitrogen application amount-d×optimum potassium application amount,Y K≈a-b×optimum nitrogen application amount-c×temperature in growth season-d×rainfall in growth season,respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships.No significant relationships:22,of which 16 were soil nutrients and 5 were environmental factors,the results showed that soil nutrients and environmental factors had little effect on nutrient conversion rate and fertilizer utilization ratio;consistent significant relationships:14,illustrating that conversion rate and utilization ratio of maize were consistent in most cases,and it was because that maize was planted for a long term,and its fertilizer absorption law was basically stable;contrary significant relationships:0,illustrating that there was no reverse relationship between conversion rate and utilization ratio of maize;complementary significant relationships:18,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the measuring index of fertilizer efficiency in one season,while the nutrient conversion rate was the measuring index of fertilizer efficiency in more seasons.It showed that the fertilizer utilization ratio was significantly correlated,or the nutrient conversion rate was significantly correlated.展开更多
Concentrated solar thermal power generation has been experimentally tested in advanced countries for a period of time.This paper demonstrates how this technology can be improved by using water molecules as a medium to...Concentrated solar thermal power generation has been experimentally tested in advanced countries for a period of time.This paper demonstrates how this technology can be improved by using water molecules as a medium to drive traditional generator sets for energy conversion,thereby simultaneously improving the energy conversion rate.Additionally,a novel contribution is made by incorporating a magic number 4 to enhance the focusing efficiency of Fresnel lenses,which drives improvements in power generation output and QE(Quantum Efficiency).展开更多
Objective:Traditional Chinese medicine plays a significant role in the treatment of the pandemic of coronavirus disease 2019(COVID-19).Tanreqing Capsule(TRQC)was used in the treatment of COVID-19 patients in the Shang...Objective:Traditional Chinese medicine plays a significant role in the treatment of the pandemic of coronavirus disease 2019(COVID-19).Tanreqing Capsule(TRQC)was used in the treatment of COVID-19 patients in the Shanghai Public Health Clinical Center.This study aimed to investigate the clinical efficacy of TRQC in the treatment of COVID-19.Methods:A retrospective cohort study was conducted on 82 patients who had laboratory-confirmed mild and moderate COVID-19;patients were treated with TRQC in one designated hospital.The treatment and control groups consisted of 25 and 57 cases,respectively.The treatment group was given TRQC orally three times a day,three pills each time,in addition to conventional Western medicine treatments which were also administered to the control group.The clinical efficacy indicators,such as the negative conversion time of pharyngeal swab nucleic acid,the negative conversion time of fecal nucleic acid,the duration of negative conversion of pharyngeal-fecal nucleic acid,and the improvement in the level of immune indicators such as T-cell subsets(CD3,CD4 and CD45)were monitored.Results:COVID-19 patients in the treatment group,compared to the control group,had a shorter negative conversion time of fecal nucleic acid(4 vs.9 days,P=0.047)and a shorter interval of negative conversion of pharyngeal-fecal nucleic acid(0 vs.2 days,P=0.042).The level of CD3+T cells increased in the treatment group compared to the control group([317.09±274.39]vs.[175.02±239.95]counts/l L,P=0.030).No statistically significant differences were detected in the median improvement in levels of CD4+T cells(173 vs.107 counts/l L,P=0.208)and CD45+T cells(366 vs.141 counts/l L,P=0.117)between the treatment and control groups.Conclusion:Significant reductions in the negative conversion time of fecal nucleic acid and the duration of negative conversion of pharyngeal-fecal nucleic acid were identified in the treatment group as compared to the control group,illustrating the potential therapeutic benefits of using TRQC as a complement to conventional medicine in patients with mild and moderate COVID-19.The underlying mechanism may be related to the improved levels of the immune indicator CD3+T cells.展开更多
On the basis of continuous tests and batch tests, conversion regular patterns of acetate, propionate and butyrate in activated sludge at different heights of the UASB reactor were conducted. Results indicated that the...On the basis of continuous tests and batch tests, conversion regular patterns of acetate, propionate and butyrate in activated sludge at different heights of the UASB reactor were conducted. Results indicated that the conversion capacity of the microbe is decided by the substrate characteristic when sole VFA is used as the only substrate. But when mixed substrates are used,the conversion regulations would have changed accordingly. Relationships of different substrates vary according to their locations. In the whole reactor, propionate's conversion is restrained by acetate and butyrate of high concentration. On the top and at the bottom of the reactor, conversion of acetate, but butyrate, is restrained by propionate. And in the midst, acetate's conversion is accelerated by propionate while that of butyrate is restrained. It is proved, based on the analysis of specific conversion rate, that the space distribution of the microbe is the main factor that affects substrates' conversion. The ethanol type fermentation of the acidogenic phase is the optimal acid type fermentation for the two phase anaerobic process.展开更多
Using 19-year satellite altimetric data, variations in the eddy kinetic energy, energy exchanges and interaction between the eddy fi eld and mean fl ow are discussed for the Kuroshio south of Japan. In the seasonal cy...Using 19-year satellite altimetric data, variations in the eddy kinetic energy, energy exchanges and interaction between the eddy fi eld and mean fl ow are discussed for the Kuroshio south of Japan. In the seasonal cycle, the eddy kinetic energy level is a minimum in December/January and a maximum in April/May. In addition to seasonal variations, the eddy kinetic energy undergoes interannual changes. The energy transfers mainly from the mean fl ow to the eddy fi eld in the Kuroshio south of Japan, and dominant energy exchanges mainly occur along the Kuroshio path south of Japan in each year from 1993 to 2011. In addition, there is often barotropic instability south of Honshu. Regarding interactions between the eddy fi eld and mean fl ow, cyclonic and anticyclonic accelerations are also found along the Kuroshio path and they fl ank each other. There is cyclonic acceleration always imposed on southeast of Kyushu, and anticyclonic acceleration dominates south of Honshu from 2001 to mid-2005. Reynolds stress is used to explain the dynamic process of energy exchange. Furthermore, lag-correlation and linear regression analysis show that variability of the energy conversion rate and Reynolds stress involve responses to eddy acceleration at two time scales. The enhanced eddy acceleration induces large Reynolds stress, and enhanced Reynolds stress or barotropic instability further enforces energy transfer from the mean fl ow to the eddy fi eld.展开更多
In order to achieve high-efficiency alkali conversion and impurity removal of high titanium slag under the condition of low alkali concentration,a new way of oxygen-rich alkali conversion in KOH solution was proposed....In order to achieve high-efficiency alkali conversion and impurity removal of high titanium slag under the condition of low alkali concentration,a new way of oxygen-rich alkali conversion in KOH solution was proposed.The conversion law of element occurrence state and the influence of the conversion conditions on the titanium conversion rate and removal rate of silicon and aluminum were studied.The results showed that the KOH solution converted the titanium oxide in high titanium slag into whisker-like potassium titanate.Silicon and aluminum elements were dissolved into the solution.Under the following conditions,KOH concentration of 6 mol/L,conversion temperature of 260℃,initial oxygen partial pressure of 2 MPa,liquid−solid ratio of 35 mL/g,conversion time of 4 h,and high titanium slag particle size of 48−74μm,the conversion rate of titanium was 97.0%,and the removal rates of silicon and aluminum were 90.2%and 76.2%,respectively.Oxygen-rich alkali conversion product was converted to rutile with a TiO_(2) grade of 99.1%by acid hydrolysis conversion.展开更多
Steam-reforming is an effective approach for upgrading methane and hydrocarbon of coke-oven gas into CO and HE, but the kinetic behavior needs more study. We investigated the conversion of methane in coke-oven gas by ...Steam-reforming is an effective approach for upgrading methane and hydrocarbon of coke-oven gas into CO and HE, but the kinetic behavior needs more study. We investigated the conversion of methane in coke-oven gas by steam reforming process in an electric tubular flow at 14 kPa with temperature varying from .500 ℃ to 9.50 ℃, and developed a kenetic model for, ignoring the effects of adsorption and diffusion. The optimal dynamic conditions for methane conversion 14 kPa are as follows： the ratio of the amount of water to the amount of methane is from 1.1 to 1.3; the reaction temperature is from 1 223 K to 1 273 K. The methane conversion rate is larger than 95% when the ratio of the amount of water to the amount of methane is 1.2 at a temperature above 1 223 K with the residence time up to 0.75 s.展开更多
The high mortality rate in hepatocellular carcinoma(HCC)is partially due to the fact that a significant number of patients are diagnosed at an intermediate or advanced stage,with surgical treatment options unavailable...The high mortality rate in hepatocellular carcinoma(HCC)is partially due to the fact that a significant number of patients are diagnosed at an intermediate or advanced stage,with surgical treatment options unavailable.Conversion therapy,which involves both locoregional and systemic treatments,has the potential to downstage tumors in selected patients with initially unresectable HCC,thereby making surgical treatment a possibility and potentially increasing long-term survival.To optimize the conversion rate,it is necessary to maximize successful conversions and clearly define the target population for conversion treatment through a collaborative effort.In this review article,we summarize the clinical experience and evidence for conversion therapy in patients with‘potentially resectable’HCC from four perspectives:1)defining the target population for conversion therapy,2)selecting the appropriate conversion strategy,placing emphasis on the utilization of combination therapy that exhibits a significant objective response rate,3)determining the timing and urgency of surgical resection,4)promoting the adoption of a multidisciplinary team model.The authors are optimistic that with the continuous progress in treatment and a deeper understanding of HCC,the success rate of HCC conversion therapy will increase,and the overall survival of HCC patients will be prolonged.展开更多
CO_(2) hydrate-based sequestration in submarine sediments shows great potential for carbon emission reduction.Considering the proportional relationship of CO_(2) and water for hydrates formation,their existing ratio l...CO_(2) hydrate-based sequestration in submarine sediments shows great potential for carbon emission reduction.Considering the proportional relationship of CO_(2) and water for hydrates formation,their existing ratio largely determines the CO_(2) sequestration density and phase state.Here,this work focuses on determining the optimal ratio of CO_(2) to seawater in sediments simulated with 20-40 mesh(0.42-0.85 mm) quartz sand,in order to maximize CO_(2) hydrate conversion in sediments.The results show that the conversion rate of CO_(2) hydrate increases with the initial water saturation,reaching 15.3%at 80% initial water saturation.The optimal CO_(2) hydrate formation occurs at 30% initial water saturation,with the corresponding CO_(2) storage density in hydrate form of 33.09 kg·m^(-3) and the hydrate saturation of 22.3%.However,CO_(2) hydrate conversion rate is <10%,which implies that most CO2 still exists in liquid state,despite the presence of free water.The total CO_(2) sequestration density is negatively correlated with the initial water saturation,and at 10% initial water saturation,398.73 kg·m^(-3) of CO_(2) is sequestered,of which only 18.02 kg·m^(-3) is hydrated.Additionally,the lower initial water saturation corresponds to the shorter time to achieve t_(90) of CO_(2) consumption,and the water conversion rate to hydrate reaches 90% at 10% initial water saturation.In summary,adjusting the volume ratio of liquid CO_(2) to seawater can effectively increase the sequestration amount of CO_(2) hydrates,but methods to increase CO_(2) conversion to hydrate still need to be established.展开更多
The effect of biochar substituted for anthracite as reductant on magnetizing-roasting pyrite cinder was in- vestigated. The key of magnetizing-roasting is the gasification reaction between reductants and CO2. Since bi...The effect of biochar substituted for anthracite as reductant on magnetizing-roasting pyrite cinder was in- vestigated. The key of magnetizing-roasting is the gasification reaction between reductants and CO2. Since biochar could react with CO2 more rapidly at lower temperature, the reactivity of biochar is better than that of anthracite. The gasification of biochar could produce reducing condition of φco/（φco--φco2 ） about 10 %- 20 % between 700-- 800 ℃, which is in accord with the atmosphere and temperature of Fe2 O3 reduction. So it is beneficial to the reduc- tion of iron mineral of pyrite cinder. Compared with anthracite, bioehar could decrease the roasting temperature from 825 to 750 ℃ and roasting time from 20 to 15 min, which shows that a better effect of magnetization could be ob- tained in the condition of lower temperature and shorter time. Using biochar as reductant, iron concentrate extracted from pyrite cinder as about 64% iron grade could be produced, and the recovery is over 90% under the condition of above 90% grinding particle less than 0. 045 mm and magnetic intensity of 0. 124--0. 194 T.展开更多
We evaluated the phenology and litterfall dynamics of the mangrove Bruguiera gymnorrhiza（L.）Lamk along the Okukubi River, Okinawa Island, Japan.Over 3 years, this species showed the highest litterfall of leaves and ...We evaluated the phenology and litterfall dynamics of the mangrove Bruguiera gymnorrhiza（L.）Lamk along the Okukubi River, Okinawa Island, Japan.Over 3 years, this species showed the highest litterfall of leaves and stipules in summer and the lowest litterfall in winter. From Kendall＇s coefficient of concordance, the monthly changes in leaf, stipule, and branch were strongly and significantly concordant among years. Leaf and stipule litterfall could be governed by monthly maximum wind speed, monthly day length, and monthly mean air temperature. Branch litterfall depended on monthly maximum wind speed and monthly rainfall, and increased exponentially with increasing monthly maximum wind speed. Mean total litterfall was 11.8 Mg ha^（-1）yr^（-1）, with the largest component being leaf litterfall（65.8 %）. Annual leaf litterfall per plot was almost constant regardless of the tree density of the plot. Mean leaf longevity was 18 months.Flower and mature propagule litterfall might be influenced by monthly mean air temperature, monthly day length and monthly mean air temperature. The average development periods from flower buds to flowers and flower buds to mature propagules were 1 and 8 months, respectively.Except for leaf and branch, all vegetative and reproductive organ litterfall had clear annual cycles. B. gymnorrhiza showed a positive correlation between leaf production and reproductive organ production.展开更多
Dielectric barrier discharge（DBD） is utilized to decompose xylene vapor in mobile gas under normal atmospheric pressure.The plasma is generated by an AC power source with a frequency of 6 kHz.In the experiment,the d...Dielectric barrier discharge（DBD） is utilized to decompose xylene vapor in mobile gas under normal atmospheric pressure.The plasma is generated by an AC power source with a frequency of 6 kHz.In the experiment,the discharge power on the DBD reactor was calculated by a Lissajous figure,and the specific input energy（SIE） of different discharge voltage or residence time was obtained.The concentrations of xylene,carbon monoxide and carbon dioxide in the gas were analyzed by gas chromatography.The spectra of DBD were diagnosed using a spectrometer.We calculated the conversion rate（CR）,mineralization rate（MR） and carbon dioxide selectivity.The relationship between these quantities and the SIE was analyzed.The experimental results show that high concentration xylene can be decomposed mostly by DBD plasma.The CR can reach as high as 90%with the main product of carbon dioxide.展开更多
The carbonation and microstructure characteristics of pellets containing ferrous dusts were investigated during carbonation consolidation at differem reaction temperatures and CO2 partial pressures. The results indica...The carbonation and microstructure characteristics of pellets containing ferrous dusts were investigated during carbonation consolidation at differem reaction temperatures and CO2 partial pressures. The results indicated that green pellets had loose and network supporting structure with initial strength, and large cracks and pores existed in the pellets. The carbonation reaction was controlled by interracial chemical reaction at the initial fast stage, which limited diffusion and thus caused the reaction rate to decrease. With increasing reaction temperature and CO2 partial pressure, the conversion rates of CaO and the number of microcrystalline CaCO3 particles increased, and the volume expansion of CaCO3 led to a decrease in the open porosity, average pore size and specific surface area of the pellets. Micro pores were occluded, and the number of smaller pores （diameter less than 50 nm） increased, thereby resulting in the more compact and uniform structure of carbonated pellets. Simuhaneously, the dense structure prevented CO2 diffusion into the product layer, affecting the increase in carbonation conversion rate.展开更多
A DBD-type （dielectric barrier discharge） NTP （non-thermal plasma） reactor was designed and an experimental system was established, in order to study the mechanism of plasma chemistry reactions in a gas mixture of...A DBD-type （dielectric barrier discharge） NTP （non-thermal plasma） reactor was designed and an experimental system was established, in order to study the mechanism of plasma chemistry reactions in a gas mixture of C3H6/NO/O2/N2. This paper is focused on a. the effects of the initial concentrations of both NO and 02 upon NO conversion rate and the variations of NOx and 03 concentrations versus SED （specific energy density） when mixed gases of NO/O2/N2 passed the NTP reactor; b. the effects of the initial concentration of C3H6 upon NO oxidation and reduction reactions in mixed gases of NO/N2/CaH6 and NO/N2/O2/C3H6. The conclusions drawn are as follows, a. When the mixed gases of NO/O2/N2 passed the NTP reactor, NO was simultaneously involved in oxidation and reduction reactions with the former dominant and NO2 concentration increased at the NTP reactor outlet. The NO conversion rate decreased with the increase of the initial concentration of NO and 02, the O3 concentration firstly increased and then decreased with the increase in SED value, b. NO reduction reaction was very weak and energy consumption was very high in a mixed gases of NO/N2. However, when C3H6 was added, the NO conversion rate was significantly increased. When 63H6 was added to the mixed gases of NO/O2/N2, the NO conversion rate was significantly increased and the energy consumption was considerably reduced.展开更多
文摘At the policy briefing held by the State Council Information Office on October 31,Guo Huanxin,Director-General of the Department of Metrology,State Administration for Market Regulation(SAMR),said that the overall conversion rate of international standards into China’s national standards has reached 86%by the end of September 2025,achieving the goal set in the National Standardization Development Outline,and providing sound support for green and low-carbon development.
文摘The conversion rates of SO2 to SO42- and NO2 to HNO3+NO3- are estimated from the field-data obtained in Beijing in summer, 1988. The results show that the conversion rate of NO2 is about four times as much as that of SO2; The conversion rates have a diurnal variation in a day. On the average, the rate of SO2 is estimated to be 4.7% h-1 during the daytime and 3.4% h-1 during the nighttime. Similarly, the rate of NO2 is estimated to be 17.2% h-1 and 12% h-1 respectively.
基金Under the auspices of the National Natural Science Foundation of China(No.40075026)
文摘Surface OH radical concentration in Beijing City was measured by impregnated filter trapping technique-high performance liquid chromatography (IFT-HPLC). The observed concentration of OH radical showed obvious diurnal and seasonal variations, with maximum readings at noon or afternoon, similar to 80x10(6)OH/cm(3) in summer and similar to 20x10(6)-40x10(6)OH/cm(3) in fall. On the basis of measured data, the reaction rates related to the photochemical process of HO(x) (OH+HO(2)) were derived and characteristics of atmospheric chemical processes in the city were analyzed. The results showed that conversion rates of atmospheric OH and HO(2) in the summer of Beijing City were about 700x10(6) molecule/(cm(3) . s) and 600x10(6)molecule/(cm(3) . s), respectively. And the net production of OH in the air of the city mainly originated from the photolysis of the gaseous HNO(2), and the main sink of OH were the photochemical reactions with VOCs, NO(2), HCHO and CO. It was different from the clean area.
基金Collaborative Innovation Task of Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences—Integration and Demonstration of Green and Efficient Agricultural Technology Innovation in Danjiangkou Water Conservation Area(CAAS-XTCX2016015)Major Scientific and Technological Projects in Guangxi(GUIKE AA17204077)+2 种基金Special Project of Guangxi Science and Technology Base and Talent(GUIKE AD18126012)First-class Discipline(Geography)Construction Project in GuangxiSpecial Funds for"Guangxi Bagui Scholars".
文摘This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for wheat by data mining method based on data of"3414 fertilizer field trials"of wheat by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of wheat for plot was that,Y N≈a+b×optimum nitrogen application amount+c×optimum fertilizer amount of K+d×rainfall in growth season,Y P≈a+b×optimum fertilizer amount of K+c×rainfall in growth season,Y K≈a+b×temperature in growth season+c×rainfall in growth season-d×optimum yield-e×optimum nitrogen application amount,respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships.No significant relationships:13,of which 8 were soil nutrients,the results showed that soil nutrients had little effect on nutrient conversion rate and fertilizer utilization ratio;consistent significant relationships:4,they were all nitrogen and phosphorus,explaining the importance of nitrogen and phosphorus;contrary significant relationships:6,they were all nitrogen and phosphorus,illustrating that phosphorus and nitrogen had inhibitory effect;complementary significant relationships:31,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the measuring index of fertilizer efficiency in one season,while the nutrient conversion rate was the measuring index of fertilizer efficiency in more seasons.It showed that the fertilizer utilization rate was significantly correlated,or the nutrient conversion rate was significantly correlated.
基金Major Scientific and Technological Projects in Guangxi(GUIKE AA17204077)Special Project of Guangxi Science and Technology Base and Talent(GUIKE AD18126012)+2 种基金First-class Discipline(Geography)Construction Project in GuangxiSpecial Funds for"Guangxi Bagui Scholars"Collaborative Innovation Task of Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences—Integration and Demonstration of Green and Efficient Agricultural Technology Innovation in Danjiangkou Water Conservation Area(CAAS-XTCX2016015).
文摘This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for rice by data mining method based on data of"3414 fertilizer field trials"of rice by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of rice for plot was that,Y N≈a+b×optimum yield+c×optimum fertilizer amount of K,Y P≈a+b×optimum yield,Y K≈a respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships:①no significant relationships:25,of which 14 were soil nutrients and 9 were environmental factors,the results showed that soil nutrients and environmental factors had little effect on nutrient yield ratio and fertilizer utilization ratio;②consistent significant relationships:2,one was that yield ratio and utilization ratio of N were positively correlated with the optimum production,explaining the importance of N for production,the other was that yield ratio and utilization ratio of P had a significantly positive correlation with conversion rate and utilization ratio of N,illustrating that nitrogen and phosphorus had mutual promotion;③contrary significant relationships:5,these showed as negative correlations of fertilizer utilization ratio and positive correlation of nutrient conversion ratio;④complementary significant relationships:22,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the index of fertilizer efficiency in one season,while the nutrient conversion rate was the index of fertilizer efficiency in more seasons,which showed that the fertilizer utilization rate was significantly correlated,or the nutrient conversion rate was significantly correlated.
基金Collaborative Innovation Task of Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences—Integration and Demonstration of Green and Efficient Agricultural Technology Innovation in Danjiangkou Water Conservation Area(CAAS-XTCX2016015)Major Scientific and Technological Projects in Guangxi(GUIKE AA17204077)+2 种基金Special Project of Guangxi Science and Technology Base and Talent(GUIKE AD18126012)First-class Discipline(Geography)Construction Project in GuangxiSpecial Funds for"Guangxi Bagui Scholars".
文摘This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of maize for plot was that,Y N≈a+b×optimum yield,Y P≈a+b×optimum yield-c×optimum nitrogen application amount-d×optimum potassium application amount,Y K≈a-b×optimum nitrogen application amount-c×temperature in growth season-d×rainfall in growth season,respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships.No significant relationships:22,of which 16 were soil nutrients and 5 were environmental factors,the results showed that soil nutrients and environmental factors had little effect on nutrient conversion rate and fertilizer utilization ratio;consistent significant relationships:14,illustrating that conversion rate and utilization ratio of maize were consistent in most cases,and it was because that maize was planted for a long term,and its fertilizer absorption law was basically stable;contrary significant relationships:0,illustrating that there was no reverse relationship between conversion rate and utilization ratio of maize;complementary significant relationships:18,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the measuring index of fertilizer efficiency in one season,while the nutrient conversion rate was the measuring index of fertilizer efficiency in more seasons.It showed that the fertilizer utilization ratio was significantly correlated,or the nutrient conversion rate was significantly correlated.
文摘Concentrated solar thermal power generation has been experimentally tested in advanced countries for a period of time.This paper demonstrates how this technology can be improved by using water molecules as a medium to drive traditional generator sets for energy conversion,thereby simultaneously improving the energy conversion rate.Additionally,a novel contribution is made by incorporating a magic number 4 to enhance the focusing efficiency of Fresnel lenses,which drives improvements in power generation output and QE(Quantum Efficiency).
基金supported by Emergency Scientific Research Project of Shanghai Health Committee and Shanghai Administration of Traditional Chinese Medicine(No.2020YJ01)Shanghai Key Laboratory of Traditional Chinese Clinical Medicine(No.14DZ2273200)Shanghai Key Clinical Specialty(No.SHSLCZDZK05101)。
文摘Objective:Traditional Chinese medicine plays a significant role in the treatment of the pandemic of coronavirus disease 2019(COVID-19).Tanreqing Capsule(TRQC)was used in the treatment of COVID-19 patients in the Shanghai Public Health Clinical Center.This study aimed to investigate the clinical efficacy of TRQC in the treatment of COVID-19.Methods:A retrospective cohort study was conducted on 82 patients who had laboratory-confirmed mild and moderate COVID-19;patients were treated with TRQC in one designated hospital.The treatment and control groups consisted of 25 and 57 cases,respectively.The treatment group was given TRQC orally three times a day,three pills each time,in addition to conventional Western medicine treatments which were also administered to the control group.The clinical efficacy indicators,such as the negative conversion time of pharyngeal swab nucleic acid,the negative conversion time of fecal nucleic acid,the duration of negative conversion of pharyngeal-fecal nucleic acid,and the improvement in the level of immune indicators such as T-cell subsets(CD3,CD4 and CD45)were monitored.Results:COVID-19 patients in the treatment group,compared to the control group,had a shorter negative conversion time of fecal nucleic acid(4 vs.9 days,P=0.047)and a shorter interval of negative conversion of pharyngeal-fecal nucleic acid(0 vs.2 days,P=0.042).The level of CD3+T cells increased in the treatment group compared to the control group([317.09±274.39]vs.[175.02±239.95]counts/l L,P=0.030).No statistically significant differences were detected in the median improvement in levels of CD4+T cells(173 vs.107 counts/l L,P=0.208)and CD45+T cells(366 vs.141 counts/l L,P=0.117)between the treatment and control groups.Conclusion:Significant reductions in the negative conversion time of fecal nucleic acid and the duration of negative conversion of pharyngeal-fecal nucleic acid were identified in the treatment group as compared to the control group,illustrating the potential therapeutic benefits of using TRQC as a complement to conventional medicine in patients with mild and moderate COVID-19.The underlying mechanism may be related to the improved levels of the immune indicator CD3+T cells.
文摘On the basis of continuous tests and batch tests, conversion regular patterns of acetate, propionate and butyrate in activated sludge at different heights of the UASB reactor were conducted. Results indicated that the conversion capacity of the microbe is decided by the substrate characteristic when sole VFA is used as the only substrate. But when mixed substrates are used,the conversion regulations would have changed accordingly. Relationships of different substrates vary according to their locations. In the whole reactor, propionate's conversion is restrained by acetate and butyrate of high concentration. On the top and at the bottom of the reactor, conversion of acetate, but butyrate, is restrained by propionate. And in the midst, acetate's conversion is accelerated by propionate while that of butyrate is restrained. It is proved, based on the analysis of specific conversion rate, that the space distribution of the microbe is the main factor that affects substrates' conversion. The ethanol type fermentation of the acidogenic phase is the optimal acid type fermentation for the two phase anaerobic process.
基金Supported by the Knowledge Innovation Program of Chinese Academy of Sciences(No.KZCX2-EW-201)the Basic Research Program of Science and Technology Projects of Qingdao(No.11-1-4-95-jch)
文摘Using 19-year satellite altimetric data, variations in the eddy kinetic energy, energy exchanges and interaction between the eddy fi eld and mean fl ow are discussed for the Kuroshio south of Japan. In the seasonal cycle, the eddy kinetic energy level is a minimum in December/January and a maximum in April/May. In addition to seasonal variations, the eddy kinetic energy undergoes interannual changes. The energy transfers mainly from the mean fl ow to the eddy fi eld in the Kuroshio south of Japan, and dominant energy exchanges mainly occur along the Kuroshio path south of Japan in each year from 1993 to 2011. In addition, there is often barotropic instability south of Honshu. Regarding interactions between the eddy fi eld and mean fl ow, cyclonic and anticyclonic accelerations are also found along the Kuroshio path and they fl ank each other. There is cyclonic acceleration always imposed on southeast of Kyushu, and anticyclonic acceleration dominates south of Honshu from 2001 to mid-2005. Reynolds stress is used to explain the dynamic process of energy exchange. Furthermore, lag-correlation and linear regression analysis show that variability of the energy conversion rate and Reynolds stress involve responses to eddy acceleration at two time scales. The enhanced eddy acceleration induces large Reynolds stress, and enhanced Reynolds stress or barotropic instability further enforces energy transfer from the mean fl ow to the eddy fi eld.
基金supported by the National Natural Science Foundation of China(Nos.U1908225,U1702253)Fundamental Research Funds for the Central Universities of China(Nos.N182515007,N170908001,N2025004)。
文摘In order to achieve high-efficiency alkali conversion and impurity removal of high titanium slag under the condition of low alkali concentration,a new way of oxygen-rich alkali conversion in KOH solution was proposed.The conversion law of element occurrence state and the influence of the conversion conditions on the titanium conversion rate and removal rate of silicon and aluminum were studied.The results showed that the KOH solution converted the titanium oxide in high titanium slag into whisker-like potassium titanate.Silicon and aluminum elements were dissolved into the solution.Under the following conditions,KOH concentration of 6 mol/L,conversion temperature of 260℃,initial oxygen partial pressure of 2 MPa,liquid−solid ratio of 35 mL/g,conversion time of 4 h,and high titanium slag particle size of 48−74μm,the conversion rate of titanium was 97.0%,and the removal rates of silicon and aluminum were 90.2%and 76.2%,respectively.Oxygen-rich alkali conversion product was converted to rutile with a TiO_(2) grade of 99.1%by acid hydrolysis conversion.
基金the Postdoctoral Foundation of China under the grant No. 2910001
文摘Steam-reforming is an effective approach for upgrading methane and hydrocarbon of coke-oven gas into CO and HE, but the kinetic behavior needs more study. We investigated the conversion of methane in coke-oven gas by steam reforming process in an electric tubular flow at 14 kPa with temperature varying from .500 ℃ to 9.50 ℃, and developed a kenetic model for, ignoring the effects of adsorption and diffusion. The optimal dynamic conditions for methane conversion 14 kPa are as follows： the ratio of the amount of water to the amount of methane is from 1.1 to 1.3; the reaction temperature is from 1 223 K to 1 273 K. The methane conversion rate is larger than 95% when the ratio of the amount of water to the amount of methane is 1.2 at a temperature above 1 223 K with the residence time up to 0.75 s.
基金Supported by the National Natural Science Foundation of China(No.82072022 and No.81771956,MZ)the Guang-Dong Basic and Applied Basic Research Foundation(No.2021A1515010403,NL).
文摘The high mortality rate in hepatocellular carcinoma(HCC)is partially due to the fact that a significant number of patients are diagnosed at an intermediate or advanced stage,with surgical treatment options unavailable.Conversion therapy,which involves both locoregional and systemic treatments,has the potential to downstage tumors in selected patients with initially unresectable HCC,thereby making surgical treatment a possibility and potentially increasing long-term survival.To optimize the conversion rate,it is necessary to maximize successful conversions and clearly define the target population for conversion treatment through a collaborative effort.In this review article,we summarize the clinical experience and evidence for conversion therapy in patients with‘potentially resectable’HCC from four perspectives:1)defining the target population for conversion therapy,2)selecting the appropriate conversion strategy,placing emphasis on the utilization of combination therapy that exhibits a significant objective response rate,3)determining the timing and urgency of surgical resection,4)promoting the adoption of a multidisciplinary team model.The authors are optimistic that with the continuous progress in treatment and a deeper understanding of HCC,the success rate of HCC conversion therapy will increase,and the overall survival of HCC patients will be prolonged.
基金financially supported by the National Natural Science Foundation of China (22378424,22127812)the Science Foundation of China University of Petroleum Beijing,China (2462023BJRC017)。
文摘CO_(2) hydrate-based sequestration in submarine sediments shows great potential for carbon emission reduction.Considering the proportional relationship of CO_(2) and water for hydrates formation,their existing ratio largely determines the CO_(2) sequestration density and phase state.Here,this work focuses on determining the optimal ratio of CO_(2) to seawater in sediments simulated with 20-40 mesh(0.42-0.85 mm) quartz sand,in order to maximize CO_(2) hydrate conversion in sediments.The results show that the conversion rate of CO_(2) hydrate increases with the initial water saturation,reaching 15.3%at 80% initial water saturation.The optimal CO_(2) hydrate formation occurs at 30% initial water saturation,with the corresponding CO_(2) storage density in hydrate form of 33.09 kg·m^(-3) and the hydrate saturation of 22.3%.However,CO_(2) hydrate conversion rate is <10%,which implies that most CO2 still exists in liquid state,despite the presence of free water.The total CO_(2) sequestration density is negatively correlated with the initial water saturation,and at 10% initial water saturation,398.73 kg·m^(-3) of CO_(2) is sequestered,of which only 18.02 kg·m^(-3) is hydrated.Additionally,the lower initial water saturation corresponds to the shorter time to achieve t_(90) of CO_(2) consumption,and the water conversion rate to hydrate reaches 90% at 10% initial water saturation.In summary,adjusting the volume ratio of liquid CO_(2) to seawater can effectively increase the sequestration amount of CO_(2) hydrates,but methods to increase CO_(2) conversion to hydrate still need to be established.
基金Item Sponsored by National Natural Science Foundation of China(51174253,51304245)
文摘The effect of biochar substituted for anthracite as reductant on magnetizing-roasting pyrite cinder was in- vestigated. The key of magnetizing-roasting is the gasification reaction between reductants and CO2. Since biochar could react with CO2 more rapidly at lower temperature, the reactivity of biochar is better than that of anthracite. The gasification of biochar could produce reducing condition of φco/（φco--φco2 ） about 10 %- 20 % between 700-- 800 ℃, which is in accord with the atmosphere and temperature of Fe2 O3 reduction. So it is beneficial to the reduc- tion of iron mineral of pyrite cinder. Compared with anthracite, bioehar could decrease the roasting temperature from 825 to 750 ℃ and roasting time from 20 to 15 min, which shows that a better effect of magnetization could be ob- tained in the condition of lower temperature and shorter time. Using biochar as reductant, iron concentrate extracted from pyrite cinder as about 64% iron grade could be produced, and the recovery is over 90% under the condition of above 90% grinding particle less than 0. 045 mm and magnetic intensity of 0. 124--0. 194 T.
基金supported by a Grant-in-Aid for Scientific Research(No.23380094)from the Ministry of Education,Culture,Sport,Science and Technology,Japan
文摘We evaluated the phenology and litterfall dynamics of the mangrove Bruguiera gymnorrhiza（L.）Lamk along the Okukubi River, Okinawa Island, Japan.Over 3 years, this species showed the highest litterfall of leaves and stipules in summer and the lowest litterfall in winter. From Kendall＇s coefficient of concordance, the monthly changes in leaf, stipule, and branch were strongly and significantly concordant among years. Leaf and stipule litterfall could be governed by monthly maximum wind speed, monthly day length, and monthly mean air temperature. Branch litterfall depended on monthly maximum wind speed and monthly rainfall, and increased exponentially with increasing monthly maximum wind speed. Mean total litterfall was 11.8 Mg ha^（-1）yr^（-1）, with the largest component being leaf litterfall（65.8 %）. Annual leaf litterfall per plot was almost constant regardless of the tree density of the plot. Mean leaf longevity was 18 months.Flower and mature propagule litterfall might be influenced by monthly mean air temperature, monthly day length and monthly mean air temperature. The average development periods from flower buds to flowers and flower buds to mature propagules were 1 and 8 months, respectively.Except for leaf and branch, all vegetative and reproductive organ litterfall had clear annual cycles. B. gymnorrhiza showed a positive correlation between leaf production and reproductive organ production.
文摘Dielectric barrier discharge（DBD） is utilized to decompose xylene vapor in mobile gas under normal atmospheric pressure.The plasma is generated by an AC power source with a frequency of 6 kHz.In the experiment,the discharge power on the DBD reactor was calculated by a Lissajous figure,and the specific input energy（SIE） of different discharge voltage or residence time was obtained.The concentrations of xylene,carbon monoxide and carbon dioxide in the gas were analyzed by gas chromatography.The spectra of DBD were diagnosed using a spectrometer.We calculated the conversion rate（CR）,mineralization rate（MR） and carbon dioxide selectivity.The relationship between these quantities and the SIE was analyzed.The experimental results show that high concentration xylene can be decomposed mostly by DBD plasma.The CR can reach as high as 90%with the main product of carbon dioxide.
基金Sponsored by National Natural Science Foundation of China(51074061)Natural Science Foundation of Hebei Province of China(E2011209039)
文摘The carbonation and microstructure characteristics of pellets containing ferrous dusts were investigated during carbonation consolidation at differem reaction temperatures and CO2 partial pressures. The results indicated that green pellets had loose and network supporting structure with initial strength, and large cracks and pores existed in the pellets. The carbonation reaction was controlled by interracial chemical reaction at the initial fast stage, which limited diffusion and thus caused the reaction rate to decrease. With increasing reaction temperature and CO2 partial pressure, the conversion rates of CaO and the number of microcrystalline CaCO3 particles increased, and the volume expansion of CaCO3 led to a decrease in the open porosity, average pore size and specific surface area of the pellets. Micro pores were occluded, and the number of smaller pores （diameter less than 50 nm） increased, thereby resulting in the more compact and uniform structure of carbonated pellets. Simuhaneously, the dense structure prevented CO2 diffusion into the product layer, affecting the increase in carbonation conversion rate.
基金supported by National Natural Science Foundation of China (No.50776041)Provincial Science Foundation of Jiangsu of China (BK2008225) Scientific Research Foundation project of Jiangsu University of China (10JDG051)
文摘A DBD-type （dielectric barrier discharge） NTP （non-thermal plasma） reactor was designed and an experimental system was established, in order to study the mechanism of plasma chemistry reactions in a gas mixture of C3H6/NO/O2/N2. This paper is focused on a. the effects of the initial concentrations of both NO and 02 upon NO conversion rate and the variations of NOx and 03 concentrations versus SED （specific energy density） when mixed gases of NO/O2/N2 passed the NTP reactor; b. the effects of the initial concentration of C3H6 upon NO oxidation and reduction reactions in mixed gases of NO/N2/CaH6 and NO/N2/O2/C3H6. The conclusions drawn are as follows, a. When the mixed gases of NO/O2/N2 passed the NTP reactor, NO was simultaneously involved in oxidation and reduction reactions with the former dominant and NO2 concentration increased at the NTP reactor outlet. The NO conversion rate decreased with the increase of the initial concentration of NO and 02, the O3 concentration firstly increased and then decreased with the increase in SED value, b. NO reduction reaction was very weak and energy consumption was very high in a mixed gases of NO/N2. However, when C3H6 was added, the NO conversion rate was significantly increased. When 63H6 was added to the mixed gases of NO/O2/N2, the NO conversion rate was significantly increased and the energy consumption was considerably reduced.
