Based on the results of field trials and soil and plant measurements, the available silicon contents ofpaddy soils, their relations with the SiO_2 content of rice plant, the relationships between rice yield on theone ...Based on the results of field trials and soil and plant measurements, the available silicon contents ofpaddy soils, their relations with the SiO_2 content of rice plant, the relationships between rice yield on theone hand and the SiO_2 content and SiO_2/N ratio of rice plant on the other, the effects of silicon on riceyield and resistance to diseases and pests and the effective conditions and causes for increasing rice yield inSichuan Basin are expounded in the present paper. The study results show that about one half of the paddysoils developed from yellow soil, purple soil, alluvial soil, etc. in Sichuan Province were insufficient in siliconsupply. Critical values for silicon fertilization were 98 mg kg￣(-1) available Si in the paddy soils and < 112.8gkg￣(-1) SiO_2 in the rice plants. A SiO_2 content of rice plant over 121.6g kg￣(-1) and a SiO_2/N ratio maintainedat about 12 were required for gaining a rice yield of 7500 kg ha￣(-1). The yield increase by silicon fertilizationwas due to the improvement of silicon nutrition in rice plants and the balance of SiO_2/N ratio, and the reasonfor enhanced resistance to diseases and pests was concerned with the inhibition of luxury N absorption andthe raising of plant SiO_2/N ratio. Silicon fertilization tended to balance the uptake of N, P and K by riceplant .展开更多
In order to validate the control effects of integrated technology of medicine and fertilizer on tobacco bacterial wilt,field experiments were conducted by using youmeili and tetracycline as the test agents.The results...In order to validate the control effects of integrated technology of medicine and fertilizer on tobacco bacterial wilt,field experiments were conducted by using youmeili and tetracycline as the test agents.The results obtained were listed as follows:(1)The incidence rate of bacterial wilt ascended more quickly after July 10 th,the incidence of CK reached 78.30%on July 25 th.(2)The control effect of“youmeili 3 g+tetramycin 200 times liquid”reached 69.47%,significantly higher than other treatments.(3)The output value of“Youmeil 3 g+tetramycin 200 times liquid”served as 1635.66 yuan/667m^2,with the highest economic character in all treatments.In a word,integrated technology of medicine and fertilizer was a feasible approach to control tobacco bacterial wilt.展开更多
The purification and separation of durene from the mixture containing durene isomers were studied.Since the boiling points of tetramethyl benzene isomers are very close but their melting points are of great difference...The purification and separation of durene from the mixture containing durene isomers were studied.Since the boiling points of tetramethyl benzene isomers are very close but their melting points are of great differences,static melt crystallization was applied to separate and purify durene from its isomers.Crystallization experiments were carried out under various operating conditions.The effects of cooling rate,crystallization temperature,sweating temperature and sweating time on the yield and purity of crystal were investigated.Orthogonal experimental design method was adopted to analyze the factors that may affect the yield of durene.Under the optimal crystallization conditions,the purity of durene could reach as high as 99.06%with the yield of 75.3%through one crystallization process.By fitting purification data based on sweating time in isothermal operations,the purification rate coefficient was obtained.展开更多
An efficient and accurate method for solving the two-dimensional Helmholtz equation in domains exterior to elongated obstacles is developed in this paper.The method is based on the so called transformed field expansio...An efficient and accurate method for solving the two-dimensional Helmholtz equation in domains exterior to elongated obstacles is developed in this paper.The method is based on the so called transformed field expansion(TFE) coupled with a spectral-Galerkin solver for elliptical domain using Mathieu functions.Numerical results are presented to show the accuracy and stability of the proposed method.展开更多
目的构建黄精炮制品多糖的酶水解产物指纹图谱,结合化学计量学方法评价不同蒸晒次数黄精炮制品多糖的差异。方法采用糖苷酶水解,结合高效薄层色谱(high thin-layer chromatography,HPTLC)、亲水作用色谱-高效液相色谱-蒸发光检测器(hydr...目的构建黄精炮制品多糖的酶水解产物指纹图谱,结合化学计量学方法评价不同蒸晒次数黄精炮制品多糖的差异。方法采用糖苷酶水解,结合高效薄层色谱(high thin-layer chromatography,HPTLC)、亲水作用色谱-高效液相色谱-蒸发光检测器(hydrophilic interaction liquid chromatography-high performance liquid chromatography-evaporative light scattering detector,HILIC-HPLC-ELSD)和超高效液相色谱-四级杆飞行时间串联质谱(ultra high pressure liquid chromatographyquadrupole time of flight tandem mass spectrometry,UHPLC-QTOF/MS)对相应的酶解产物进行高效分离和检测。由此产生的自下而上的指纹图谱反映了黄精炮制品多糖的变化,通过相似度和偏最小二乘-判别分析(partial least squares-discriminant analysis,PLS-DA)对指纹图谱进行综合评价。结果HPTLC分析发现,果糖随着蒸晒次数的增加逐渐降低,结合色谱分析发现,六蒸六晒和十二蒸十二晒为黄精炮制过程中的转折点。同时根据酶水解中寡糖的变化,利用相似度和PLS-DA对不同蒸晒次数的黄精炮制品进行了清晰的聚类。结合UHPLC-QTOF/MS分析表明,不同蒸晒次数黄精炮制品中含有蔗糖、蔗果三糖、蔗果四糖、蔗果五糖、蔗果六糖、蔗果七糖及蔗果八糖。结论基于酶解法分析不同蒸晒次数样品的质量动态变化,结合所建立的多元指纹图谱,进一步阐释了不同蒸晒次数黄精炮制品的科学内涵。展开更多
The main aim of this paper is to study the convergence of biquadratic finite element tor the second order problem on anisotropic meshes. By using some novel approaches and techniques, the optimal error estimates are o...The main aim of this paper is to study the convergence of biquadratic finite element tor the second order problem on anisotropic meshes. By using some novel approaches and techniques, the optimal error estimates are obtuined. At the same time, the anisotropic superclose results are also achieved. Furthermore, the numerical results are given to demonstrate our theoretical analysis.展开更多
文摘Based on the results of field trials and soil and plant measurements, the available silicon contents ofpaddy soils, their relations with the SiO_2 content of rice plant, the relationships between rice yield on theone hand and the SiO_2 content and SiO_2/N ratio of rice plant on the other, the effects of silicon on riceyield and resistance to diseases and pests and the effective conditions and causes for increasing rice yield inSichuan Basin are expounded in the present paper. The study results show that about one half of the paddysoils developed from yellow soil, purple soil, alluvial soil, etc. in Sichuan Province were insufficient in siliconsupply. Critical values for silicon fertilization were 98 mg kg￣(-1) available Si in the paddy soils and < 112.8gkg￣(-1) SiO_2 in the rice plants. A SiO_2 content of rice plant over 121.6g kg￣(-1) and a SiO_2/N ratio maintainedat about 12 were required for gaining a rice yield of 7500 kg ha￣(-1). The yield increase by silicon fertilizationwas due to the improvement of silicon nutrition in rice plants and the balance of SiO_2/N ratio, and the reasonfor enhanced resistance to diseases and pests was concerned with the inhibition of luxury N absorption andthe raising of plant SiO_2/N ratio. Silicon fertilization tended to balance the uptake of N, P and K by riceplant .
基金Supported by Science and Technology Project of Yunnan Tobacco Company(2015YN07,2017YN26)~~
文摘In order to validate the control effects of integrated technology of medicine and fertilizer on tobacco bacterial wilt,field experiments were conducted by using youmeili and tetracycline as the test agents.The results obtained were listed as follows:(1)The incidence rate of bacterial wilt ascended more quickly after July 10 th,the incidence of CK reached 78.30%on July 25 th.(2)The control effect of“youmeili 3 g+tetramycin 200 times liquid”reached 69.47%,significantly higher than other treatments.(3)The output value of“Youmeil 3 g+tetramycin 200 times liquid”served as 1635.66 yuan/667m^2,with the highest economic character in all treatments.In a word,integrated technology of medicine and fertilizer was a feasible approach to control tobacco bacterial wilt.
基金Supported by the National Natural Science Foundation of China(21176172)Top Talents Program of Yunnan Province,China(2011HA010)
文摘The purification and separation of durene from the mixture containing durene isomers were studied.Since the boiling points of tetramethyl benzene isomers are very close but their melting points are of great differences,static melt crystallization was applied to separate and purify durene from its isomers.Crystallization experiments were carried out under various operating conditions.The effects of cooling rate,crystallization temperature,sweating temperature and sweating time on the yield and purity of crystal were investigated.Orthogonal experimental design method was adopted to analyze the factors that may affect the yield of durene.Under the optimal crystallization conditions,the purity of durene could reach as high as 99.06%with the yield of 75.3%through one crystallization process.By fitting purification data based on sweating time in isothermal operations,the purification rate coefficient was obtained.
基金supported in part by NSF grant DMS-0610646supported by AcRF Tier 1 Grant RG58/08+1 种基金Singapore MOE Grant T207B2202Singapore NRF2007IDM-IDM002-010
文摘An efficient and accurate method for solving the two-dimensional Helmholtz equation in domains exterior to elongated obstacles is developed in this paper.The method is based on the so called transformed field expansion(TFE) coupled with a spectral-Galerkin solver for elliptical domain using Mathieu functions.Numerical results are presented to show the accuracy and stability of the proposed method.
文摘目的构建黄精炮制品多糖的酶水解产物指纹图谱,结合化学计量学方法评价不同蒸晒次数黄精炮制品多糖的差异。方法采用糖苷酶水解,结合高效薄层色谱(high thin-layer chromatography,HPTLC)、亲水作用色谱-高效液相色谱-蒸发光检测器(hydrophilic interaction liquid chromatography-high performance liquid chromatography-evaporative light scattering detector,HILIC-HPLC-ELSD)和超高效液相色谱-四级杆飞行时间串联质谱(ultra high pressure liquid chromatographyquadrupole time of flight tandem mass spectrometry,UHPLC-QTOF/MS)对相应的酶解产物进行高效分离和检测。由此产生的自下而上的指纹图谱反映了黄精炮制品多糖的变化,通过相似度和偏最小二乘-判别分析(partial least squares-discriminant analysis,PLS-DA)对指纹图谱进行综合评价。结果HPTLC分析发现,果糖随着蒸晒次数的增加逐渐降低,结合色谱分析发现,六蒸六晒和十二蒸十二晒为黄精炮制过程中的转折点。同时根据酶水解中寡糖的变化,利用相似度和PLS-DA对不同蒸晒次数的黄精炮制品进行了清晰的聚类。结合UHPLC-QTOF/MS分析表明,不同蒸晒次数黄精炮制品中含有蔗糖、蔗果三糖、蔗果四糖、蔗果五糖、蔗果六糖、蔗果七糖及蔗果八糖。结论基于酶解法分析不同蒸晒次数样品的质量动态变化,结合所建立的多元指纹图谱,进一步阐释了不同蒸晒次数黄精炮制品的科学内涵。
基金The research is supported by National Science Foundation of China under Grant No.10371113Foundation of Overseas Scholar of China under Grant No.(2002)119the Project of the Creative Engineering of Henan Province of China.
文摘The main aim of this paper is to study the convergence of biquadratic finite element tor the second order problem on anisotropic meshes. By using some novel approaches and techniques, the optimal error estimates are obtuined. At the same time, the anisotropic superclose results are also achieved. Furthermore, the numerical results are given to demonstrate our theoretical analysis.
