铝渣中的氮化铝(AlN)在潮湿的空气中会水解,释放出大量的氨气。氨气长时间暴露在空气中会危害环境和损害人体健康,但经有效处置可回收利用。本文针对AlN水解存在反应时间长、反应不彻底的特点,研究了反应温度、液固比和反应时间对水解...铝渣中的氮化铝(AlN)在潮湿的空气中会水解,释放出大量的氨气。氨气长时间暴露在空气中会危害环境和损害人体健康,但经有效处置可回收利用。本文针对AlN水解存在反应时间长、反应不彻底的特点,研究了反应温度、液固比和反应时间对水解行为的影响,并采用响应曲面法对实验条件进行了优化。在最佳实验条件下:反应温度95℃、反应时间11.2 h、液固比7.8:1 m L/g、搅拌速度400 r/min,AlN水解率为92.45%。反应动力学研究表明,水解过程由表面化学反应控制模型控制,表观活化能为40.24 k J/mol。XRD和SEM-EDS结果显示,AlN最终转化为Al(OH)_(3)附着在铝渣的表面,晶体随温度和时间的增加逐渐增大。本文结果为从铝渣中回收氨气提供了有效的参考。展开更多
First,using the law of large numbers,I analyze the setting principle of agricultural insurance premium rate,and take the case of setting of adult sow premium rate for study,to draw the conclusion that with the continu...First,using the law of large numbers,I analyze the setting principle of agricultural insurance premium rate,and take the case of setting of adult sow premium rate for study,to draw the conclusion that with the continuous promotion of agricultural insurance,increase in the types of agricultural insurance and increase in the number of the insured,the premium rate should also be adjusted opportunely.Then,on the basis of Bayes' theorem,I adjust and calibrate the claim frequency and the average claim,in order to correctly adjust agricultural insurance premium rate;take the case of forest insurance for premium rate adjustment analysis.In setting and adjustment of agricultural insurance premium rate,in order to make the expected results well close to the real results,it is necessary to apply the probability estimates in a large number of risk units;focus on the establishment of agricultural risk database,to timely adjust agricultural insurance premium rate.展开更多
Background Glaucoma is one of the leading causes of blindness in the world. Primary open-angle glaucoma （POAG） and primary congenital glaucoma （PCG） are subtypes of glaucoma. Myocillin is the first gene identified...Background Glaucoma is one of the leading causes of blindness in the world. Primary open-angle glaucoma （POAG） and primary congenital glaucoma （PCG） are subtypes of glaucoma. Myocillin is the first gene identified to be involved in POAG. Recently, myocillin mutation has been found in PCG. In this context, we reported a special glaucoma pedigree, which was composed of both PCG and POAG patients, and analyzed the mutation of myocillin in this pedigree. Methods The family was composed of the parents, a son and a daughter. All members of the family underwent the complete ophthalmologic examinations. All coding exons 1-3 and flanking introns of myocilin gene were screened for sequence alterations by polymerase chain reaction and direct DNA sequencing. Results The son was the proband, who was diagnosed as PCG in both eyes. The father was diagnosed as POAG in the right eye, the left eye was still normal. Both the sister and the mother of the proband had normal intraocular pressure without glaucomatous optic disc changes. The mutations in intron 2 of myocilin gene were detected in the family. While the proband and the father were homozygous, the mother and the sister were heterozygous for the mutation. Conclusions Homozygous mutation in intron 2 of myocilin gene is involved in both POAG and PCG. It is suggested that the pathogenesis might be overlapping in POAG and PCG.展开更多
基金Project(51874356) supported by the National Natural Science Foundation of ChinaProjects(2020YFC1909203, 2018YFC1902500) supported by the National Key Research and Development Program of China。
文摘铝渣中的氮化铝(AlN)在潮湿的空气中会水解,释放出大量的氨气。氨气长时间暴露在空气中会危害环境和损害人体健康,但经有效处置可回收利用。本文针对AlN水解存在反应时间长、反应不彻底的特点,研究了反应温度、液固比和反应时间对水解行为的影响,并采用响应曲面法对实验条件进行了优化。在最佳实验条件下:反应温度95℃、反应时间11.2 h、液固比7.8:1 m L/g、搅拌速度400 r/min,AlN水解率为92.45%。反应动力学研究表明,水解过程由表面化学反应控制模型控制,表观活化能为40.24 k J/mol。XRD和SEM-EDS结果显示,AlN最终转化为Al(OH)_(3)附着在铝渣的表面,晶体随温度和时间的增加逐渐增大。本文结果为从铝渣中回收氨气提供了有效的参考。
基金Supported by National Excellent Doctoral Dissertation Cultivation Fund Project,Hunan Agricultural University (GYB201003)
文摘First,using the law of large numbers,I analyze the setting principle of agricultural insurance premium rate,and take the case of setting of adult sow premium rate for study,to draw the conclusion that with the continuous promotion of agricultural insurance,increase in the types of agricultural insurance and increase in the number of the insured,the premium rate should also be adjusted opportunely.Then,on the basis of Bayes' theorem,I adjust and calibrate the claim frequency and the average claim,in order to correctly adjust agricultural insurance premium rate;take the case of forest insurance for premium rate adjustment analysis.In setting and adjustment of agricultural insurance premium rate,in order to make the expected results well close to the real results,it is necessary to apply the probability estimates in a large number of risk units;focus on the establishment of agricultural risk database,to timely adjust agricultural insurance premium rate.
基金This work was supported by a grant from the Foundation for Authors of National Excellent Doctoral Dissertation of China (No.200363).
文摘Background Glaucoma is one of the leading causes of blindness in the world. Primary open-angle glaucoma （POAG） and primary congenital glaucoma （PCG） are subtypes of glaucoma. Myocillin is the first gene identified to be involved in POAG. Recently, myocillin mutation has been found in PCG. In this context, we reported a special glaucoma pedigree, which was composed of both PCG and POAG patients, and analyzed the mutation of myocillin in this pedigree. Methods The family was composed of the parents, a son and a daughter. All members of the family underwent the complete ophthalmologic examinations. All coding exons 1-3 and flanking introns of myocilin gene were screened for sequence alterations by polymerase chain reaction and direct DNA sequencing. Results The son was the proband, who was diagnosed as PCG in both eyes. The father was diagnosed as POAG in the right eye, the left eye was still normal. Both the sister and the mother of the proband had normal intraocular pressure without glaucomatous optic disc changes. The mutations in intron 2 of myocilin gene were detected in the family. While the proband and the father were homozygous, the mother and the sister were heterozygous for the mutation. Conclusions Homozygous mutation in intron 2 of myocilin gene is involved in both POAG and PCG. It is suggested that the pathogenesis might be overlapping in POAG and PCG.
