阅读英语书刊时经常会遇到这样的句子:1.The 5th century saw the end of the Roman Empire in the west. 第五世纪西罗马帝国灭亡了。2.When he had to speak to her his courae suddenly deserted him. 当他不得不和她说话时,他突然...阅读英语书刊时经常会遇到这样的句子:1.The 5th century saw the end of the Roman Empire in the west. 第五世纪西罗马帝国灭亡了。2.When he had to speak to her his courae suddenly deserted him. 当他不得不和她说话时,他突然失去了勇气。3.His illness prevnted him from joining the expedition.展开更多
[Objective]The research aimed to study the biomass structure of the functional modules of clonal population of Puccinellia tenuifora on Songnen Plain and its relationship with the functional modules quantitatively.[Me...[Objective]The research aimed to study the biomass structure of the functional modules of clonal population of Puccinellia tenuifora on Songnen Plain and its relationship with the functional modules quantitatively.[Method]Using the sample method of digging up the whole tiller tuft randomly at flowering stage,the relationships between the biomass of functional modules and turf size,biomass of different modules and the clone production,reproductive tillers of clones and the biomass of component modules of Puccinellia tenuifora clones on Songnen Plain were quantitatively analyzed.[Result]The biomass of sexual reproductive module,photosynthesis module and supporting module showed a linear increase with the increasing of turf size（P 〈0.05）,while the linear relationship between the biomass of vegetative reproductive module and turf size did not reach the significant level（P 〉0.05）.The restriction degree of turf size on the biomass of functional modules was supporting module sexual reproductive module photosynthesis module vegetative reproductive module.Biomass of reproductive tillers and vegetative tillers showed a linear increase as the biomass of total modules increased（P〈 0.05）,while the linear correlation between the biomass of tillering seedlings and biomass of total modules did not reach the significant level（P 〉0.05）.Biomass of stem,spike and leaf of reproductive plants showed a linear functional increase as reproductive tiller increased（P 〈0.05）,and the ratio of accumulation of biomass of stem,spike and leaf was 7：2：1.[Conclusion]The research laid the theoretical foundation for the further research on the ecology of clustered clone plants.展开更多
Eleven tertiarv alkaloids were isolated from Corvdalis decumbens rhizome Their structures were identified as protopine(Ⅶ),allocryptopine(Ⅷ),cryptopine (Ⅸ),muramine(ⅩⅦ);(+)-tetrahydropalmatine(Ⅲ),(+)-kikemanine (...Eleven tertiarv alkaloids were isolated from Corvdalis decumbens rhizome Their structures were identified as protopine(Ⅶ),allocryptopine(Ⅷ),cryptopine (Ⅸ),muramine(ⅩⅦ);(+)-tetrahydropalmatine(Ⅲ),(+)-kikemanine (Ⅳ),(一)-scoulerine (ⅩⅧ),(十)-bulbo- capnine (ⅩⅨ),and(一)一capnoidine(Ⅰ),(一)一bicuculline(Ⅴ),(+) coriumidine(ⅩⅣ), respecti vely。 Among these,cryptopine,muramine,(+)-kikemanine,(-)-scoulerine,(一)capnoidine,(一)一bicuculline were isolated for the first time from this plant展开更多
The quality of straw affects N release after straw retention. As straw with high C： N ratio could result in N immobilization, additional N is needed to compensate N demand of crops. However, more and more N fertilize...The quality of straw affects N release after straw retention. As straw with high C： N ratio could result in N immobilization, additional N is needed to compensate N demand of crops. However, more and more N fertilizers have been applied to the soil to improve crop yields in China, which not only increases production cost but also reduces soil quality. Therefore, reasonable application of N fertilizer becomes a key problem after straw retention. This study aimed to assess the effects of applying maize straw with high quality alfalfa straw on mineral N content, microbial biomass and enzyme activity under controlled conditions. The effect of applying maize straw with alfalfa straw was compared with that of maize straw in combination with N fertilizer under the same C： N ratio （25：1）. The laboratory incubation experiment consisted of four treatments： （1） soil with no addition （CK）; （2） soil amended with maize straw （M）; （3） soil amended with alfalfa straw and maize straw with an adjusted C： N ratio of 25：1 （MM）; （4） soil amended with inorganic nitrogen fertilizer and maize straw with an adjusted C：N ratio of 25：1 （MF）. The results showed that application of maize straw leaded to an N immobilization during the 270 d of incubation. Combined application of alfalfa and maize straw and or mineral N fertilizer alleviates the N immobilization and increase soil mineral N content. Compared to MF treatment, MM treatment prolonged N availability during the incubation. MM and MF treatments increased the soil microbial biomass carbon and nitrogen contents, and soil invertase and β-glycosidase activities. There was no difference between MM and M treatment in soil urease activity. MF treatment had significantly negative influence on soil urease activity compared with M treatment. The amount of added N significantly affected mineral N content, soil microbial biomass and enzyme activity. The mixture of alfalfa straw and maize straw sustains higher level of mineral N content, microbial biomass and enzyme activity as it had high N input compared to maize straw in combination with N fertilizer. It is concluded that alfalfa straw may be a better N source than N fertilizer in alleviating N immobilization caused by maize straw retention.展开更多
The exotic Sonneratia apetala in Leizhou Peninsula, has shown outstanding fast-growing ability in restored mangrove forests, at the middle and high tide intertidal zone, with year-round fresh water input from drainage...The exotic Sonneratia apetala in Leizhou Peninsula, has shown outstanding fast-growing ability in restored mangrove forests, at the middle and high tide intertidal zone, with year-round fresh water input from drainage. By setting plot and selecting standard tree, investigation and measurement on height growth, diameter growth, biomass, productivity, and so on, were made in a S. apetala plantation at age of six at Lanbei, Fucheng, Leizhou Peninsula in May 2001. The investigating results showed that the mean annual height growth of plantation was 2.03 m and mean annual growth of diameter at breast height (DBH) was 2.35 cm. There exists a significant correlation between the diameter at ground surface (DGS) and DBH. The average biomass of a single standard tree in dry weight was 95.647 kg/m2. A ratio of above-ground biomass to under-ground biomass was 1.60. The stand biomass of unit area was 22.955 kg/m2, singletree wood volume was 88.23 dm3, and the annual wood volume productivity (PA) of the same year was 0.407. The forest energy accumulation was 424.851 MJ/m2, with annual solar energy fixing rate of 40.68 ×10-7%. It is concluded that S. apetala species had characteristics of outstanding high biomass accumulation and could be used as coastal planting tree species in southern China.展开更多
This paper summarizes a nontoxic Anti-fouling coating utilizing capsaicin as an anti-fouling agent. The capsaicin constituent used in the coating has a rating from about 100 000 to about 1 500 000 Scoville Heat Units....This paper summarizes a nontoxic Anti-fouling coating utilizing capsaicin as an anti-fouling agent. The capsaicin constituent used in the coating has a rating from about 100 000 to about 1 500 000 Scoville Heat Units. The capsaicin is mixed with a silicon dioxide and then solubilized into a free-flowing homogeneous liquid oleoresin composition by adding a solvent to increase solubility and facilitate mixing. The oleoresin capsaicin liquid solution is mixed with a suitable corrosion resistant epoxy resin, which is then mixed with a hardening catalyst and applied to the surface to be treated.展开更多
在高中英语课本第一册第五课上,有这样一个句子:Dusk found him crying inthe street…我们发现,dusk虽然在旬中充当了主语成分,但在意义上却不是动作的发出者。句子的重心放在了 him 和 crying 上面,这种由无生命事物充当的句子主语叫...在高中英语课本第一册第五课上,有这样一个句子:Dusk found him crying inthe street…我们发现,dusk虽然在旬中充当了主语成分,但在意义上却不是动作的发出者。句子的重心放在了 him 和 crying 上面,这种由无生命事物充当的句子主语叫做无生物主语。一般说来,无生物主语,其谓语动词多含有使令性意义或表示某种结果。例如:make,enable,bring,keep,remind,prevent,show,etc.展开更多
An upflow mode membrane-less microbial fuel cell （ML-MFC） was designed for wastewater treatment. Granular graphite electrodes, which are flexible in size, were adopted in the ML-MFC. Microbes present in anaerobic ac...An upflow mode membrane-less microbial fuel cell （ML-MFC） was designed for wastewater treatment. Granular graphite electrodes, which are flexible in size, were adopted in the ML-MFC. Microbes present in anaerobic activated sludge were used as the biocatalyst and artificial wastewater was tested as substrate. During the electrochemically active microbe enrichment stage, a stable power output of 536 mW.m-3 with reference to the anode volume was generated by the ML-MFC running in batch mode. The voltage output decreased from 203 mV to about 190 mV after the ML-MFC was changed from batch mode to normally continuous mode, indicating that planktonic electrochemically active bacterial strains in the ML-MFC may be carried away along with the effluent. Cyclic voltammograms showed that the attached microbes possessed higher bioelectrochemical activity than the planktonic microbes. Forced aeration to the cathode benefited the electricity generation obviously. Higher feeding rate and longer electrode distance both increased the electricity generation. The coulombic yield was not more than 20% throughout the study, which is lower than that of MFCs with membrane. It is proposed that dissolved oxygen diffused from the cathode to the anode may consume part of the substrate.展开更多
文摘阅读英语书刊时经常会遇到这样的句子:1.The 5th century saw the end of the Roman Empire in the west. 第五世纪西罗马帝国灭亡了。2.When he had to speak to her his courae suddenly deserted him. 当他不得不和她说话时,他突然失去了勇气。3.His illness prevnted him from joining the expedition.
基金Suppported by National High Technology Research and Development Program of China (2008AA10Z224)National Natural Science Foundation of China(30960261,30700055)Ph. D. Programs Foundation of Ministry of Education of China(20070200005)~~
文摘[Objective]The research aimed to study the biomass structure of the functional modules of clonal population of Puccinellia tenuifora on Songnen Plain and its relationship with the functional modules quantitatively.[Method]Using the sample method of digging up the whole tiller tuft randomly at flowering stage,the relationships between the biomass of functional modules and turf size,biomass of different modules and the clone production,reproductive tillers of clones and the biomass of component modules of Puccinellia tenuifora clones on Songnen Plain were quantitatively analyzed.[Result]The biomass of sexual reproductive module,photosynthesis module and supporting module showed a linear increase with the increasing of turf size（P 〈0.05）,while the linear relationship between the biomass of vegetative reproductive module and turf size did not reach the significant level（P 〉0.05）.The restriction degree of turf size on the biomass of functional modules was supporting module sexual reproductive module photosynthesis module vegetative reproductive module.Biomass of reproductive tillers and vegetative tillers showed a linear increase as the biomass of total modules increased（P〈 0.05）,while the linear correlation between the biomass of tillering seedlings and biomass of total modules did not reach the significant level（P 〉0.05）.Biomass of stem,spike and leaf of reproductive plants showed a linear functional increase as reproductive tiller increased（P 〈0.05）,and the ratio of accumulation of biomass of stem,spike and leaf was 7：2：1.[Conclusion]The research laid the theoretical foundation for the further research on the ecology of clustered clone plants.
文摘Eleven tertiarv alkaloids were isolated from Corvdalis decumbens rhizome Their structures were identified as protopine(Ⅶ),allocryptopine(Ⅷ),cryptopine (Ⅸ),muramine(ⅩⅦ);(+)-tetrahydropalmatine(Ⅲ),(+)-kikemanine (Ⅳ),(一)-scoulerine (ⅩⅧ),(十)-bulbo- capnine (ⅩⅨ),and(一)一capnoidine(Ⅰ),(一)一bicuculline(Ⅴ),(+) coriumidine(ⅩⅣ), respecti vely。 Among these,cryptopine,muramine,(+)-kikemanine,(-)-scoulerine,(一)capnoidine,(一)一bicuculline were isolated for the first time from this plant
文摘The quality of straw affects N release after straw retention. As straw with high C： N ratio could result in N immobilization, additional N is needed to compensate N demand of crops. However, more and more N fertilizers have been applied to the soil to improve crop yields in China, which not only increases production cost but also reduces soil quality. Therefore, reasonable application of N fertilizer becomes a key problem after straw retention. This study aimed to assess the effects of applying maize straw with high quality alfalfa straw on mineral N content, microbial biomass and enzyme activity under controlled conditions. The effect of applying maize straw with alfalfa straw was compared with that of maize straw in combination with N fertilizer under the same C： N ratio （25：1）. The laboratory incubation experiment consisted of four treatments： （1） soil with no addition （CK）; （2） soil amended with maize straw （M）; （3） soil amended with alfalfa straw and maize straw with an adjusted C： N ratio of 25：1 （MM）; （4） soil amended with inorganic nitrogen fertilizer and maize straw with an adjusted C：N ratio of 25：1 （MF）. The results showed that application of maize straw leaded to an N immobilization during the 270 d of incubation. Combined application of alfalfa and maize straw and or mineral N fertilizer alleviates the N immobilization and increase soil mineral N content. Compared to MF treatment, MM treatment prolonged N availability during the incubation. MM and MF treatments increased the soil microbial biomass carbon and nitrogen contents, and soil invertase and β-glycosidase activities. There was no difference between MM and M treatment in soil urease activity. MF treatment had significantly negative influence on soil urease activity compared with M treatment. The amount of added N significantly affected mineral N content, soil microbial biomass and enzyme activity. The mixture of alfalfa straw and maize straw sustains higher level of mineral N content, microbial biomass and enzyme activity as it had high N input compared to maize straw in combination with N fertilizer. It is concluded that alfalfa straw may be a better N source than N fertilizer in alleviating N immobilization caused by maize straw retention.
基金The paper was supported by the project of integrated mangrove management and coastal protection(IMMCP) in Leizhou Peninsula Guangdong Province.
文摘The exotic Sonneratia apetala in Leizhou Peninsula, has shown outstanding fast-growing ability in restored mangrove forests, at the middle and high tide intertidal zone, with year-round fresh water input from drainage. By setting plot and selecting standard tree, investigation and measurement on height growth, diameter growth, biomass, productivity, and so on, were made in a S. apetala plantation at age of six at Lanbei, Fucheng, Leizhou Peninsula in May 2001. The investigating results showed that the mean annual height growth of plantation was 2.03 m and mean annual growth of diameter at breast height (DBH) was 2.35 cm. There exists a significant correlation between the diameter at ground surface (DGS) and DBH. The average biomass of a single standard tree in dry weight was 95.647 kg/m2. A ratio of above-ground biomass to under-ground biomass was 1.60. The stand biomass of unit area was 22.955 kg/m2, singletree wood volume was 88.23 dm3, and the annual wood volume productivity (PA) of the same year was 0.407. The forest energy accumulation was 424.851 MJ/m2, with annual solar energy fixing rate of 40.68 ×10-7%. It is concluded that S. apetala species had characteristics of outstanding high biomass accumulation and could be used as coastal planting tree species in southern China.
文摘This paper summarizes a nontoxic Anti-fouling coating utilizing capsaicin as an anti-fouling agent. The capsaicin constituent used in the coating has a rating from about 100 000 to about 1 500 000 Scoville Heat Units. The capsaicin is mixed with a silicon dioxide and then solubilized into a free-flowing homogeneous liquid oleoresin composition by adding a solvent to increase solubility and facilitate mixing. The oleoresin capsaicin liquid solution is mixed with a suitable corrosion resistant epoxy resin, which is then mixed with a hardening catalyst and applied to the surface to be treated.
文摘在高中英语课本第一册第五课上,有这样一个句子:Dusk found him crying inthe street…我们发现,dusk虽然在旬中充当了主语成分,但在意义上却不是动作的发出者。句子的重心放在了 him 和 crying 上面,这种由无生命事物充当的句子主语叫做无生物主语。一般说来,无生物主语,其谓语动词多含有使令性意义或表示某种结果。例如:make,enable,bring,keep,remind,prevent,show,etc.
基金Supported by the National Natural Science Foundation of China （20306029, 20576137）.
文摘An upflow mode membrane-less microbial fuel cell （ML-MFC） was designed for wastewater treatment. Granular graphite electrodes, which are flexible in size, were adopted in the ML-MFC. Microbes present in anaerobic activated sludge were used as the biocatalyst and artificial wastewater was tested as substrate. During the electrochemically active microbe enrichment stage, a stable power output of 536 mW.m-3 with reference to the anode volume was generated by the ML-MFC running in batch mode. The voltage output decreased from 203 mV to about 190 mV after the ML-MFC was changed from batch mode to normally continuous mode, indicating that planktonic electrochemically active bacterial strains in the ML-MFC may be carried away along with the effluent. Cyclic voltammograms showed that the attached microbes possessed higher bioelectrochemical activity than the planktonic microbes. Forced aeration to the cathode benefited the electricity generation obviously. Higher feeding rate and longer electrode distance both increased the electricity generation. The coulombic yield was not more than 20% throughout the study, which is lower than that of MFCs with membrane. It is proposed that dissolved oxygen diffused from the cathode to the anode may consume part of the substrate.
