The photo-induced electron transfer reactions of anthracene with N,N -diethylaniline(DEA) and phenothiazine(PTZ) occur in the membrane phase of a Triton X-100/ n -C 10 H 21 OH(1-decanol)/H 2O microemulsion. DEA and PT...The photo-induced electron transfer reactions of anthracene with N,N -diethylaniline(DEA) and phenothiazine(PTZ) occur in the membrane phase of a Triton X-100/ n -C 10 H 21 OH(1-decanol)/H 2O microemulsion. DEA and PTZ exist in the membrane phase of the microemulsion. Anthracene exists in the oil continuous phase of the W/O microemulsion and in the oil core and membrane phase of the O/W microemulsion.展开更多
A lab-incubation experiment was conducted to investigate the effects of different forms of nitrogen application (ammonium, NH4+-N; nitrate, NO3--N; and amide-N, NH2-N) and different concentrations (40, 200 and 800...A lab-incubation experiment was conducted to investigate the effects of different forms of nitrogen application (ammonium, NH4+-N; nitrate, NO3--N; and amide-N, NH2-N) and different concentrations (40, 200 and 800 mg L-1) on N2O emission from the fluvo-aquic soil subjected to a freezing-thawing cycling. N2O emission sharply decreased at the start of soil freezing, and then showed a smooth line with soil freezing. In subject to soil thawing, N2O emission increased and reached a peak at the initial thawing stage. The average N2O emissions with addition of NH4+-N, NO3 -N and NH2-N are 119.01, 611.61 and 148. 22 ug m-2 h-1, respectively, at the concentration of 40 mg L-1; 205.28, 1 084.40 and 106.13 ug m2 h-1 at the concentration of 200 mg L-1; and 693.95, 1 820.02 and 49.74 ug m-2 h4 at the concentration of 800 mg L-1. The control is only 100.35 ug m-2 h-1. N2O emissions with addition of NH4+-N and NO3--N increased with increasing concentration, by ranging from 17.49 to 425.67% for NH4+-N, and from 563.38 to 1458.6% for NO3--N compared with control. There was a timelag for N2O emission to reach a steady state with an increase of concentration. In contrast, by adding NH2-N to soil, N2O emission decreased with increasing concentration. In sum, NH4+-N or NO3--N fertilizer incorporated in soil enhanced the cumulative N2O emission from the fluvo-aquic soil relative to amide-N. This study suggested that ammonium and nitrate concentration in overwintering water should be less than 200 and 40 mg L-1 in order to reduce N2O emissions from soil, regardless of amide-N.展开更多
In this article, authors discuss the problem of uniform packing dimension of the image set of multiparameter stochastic processes without random uniform Holder condition, and obtain the uniform packing dimension of mu...In this article, authors discuss the problem of uniform packing dimension of the image set of multiparameter stochastic processes without random uniform Holder condition, and obtain the uniform packing dimension of multiparameter stable processes. If Z is a stable (N, d, α)-process and αN ≤ d, then the following holds with probability 1 Dim Z(E)=α Dim E for any Borel setE ∈B(R +^N), where Z(E)={x:E←t∈E,Z(t)=x}, Dim (E) denotes the packing dimension of E.展开更多
The numerical control (NC) precision bending process of thin-walled tube is on e of advanced plastic forming processes with high efficiency, forming precision, strength/weight ratio and low cost, thus it is playing mo...The numerical control (NC) precision bending process of thin-walled tube is on e of advanced plastic forming processes with high efficiency, forming precision, strength/weight ratio and low cost, thus it is playing more and more important role in manufacturing parts in aerospace and automobile industries. However, the determination of parameters crucial to make sure tube parts qualified is heavil y experience-based and involves repeated trial-and-errors in practice, which makes the production efficiency reduce drastically and does not fulfill the deve lopment of high technology. With quick development of computer technology and gr adual perfect of plastic forming theory, computer numerical simulation based on finite element method (FEM) has become one of important tools of researching and developing plastic forming technology. Development trend of NC precision bendin g process of tube is simulating its forming process by FEM. Because NC tube bend ing is of 3D nature, it is of great importance to analyze the forming mechanism and find out the influence law of forming parameters on forming process in the N C precision bending process of thin-walled tube quantitatively by 3D FE simulat ion. Based on the rigid-plastic finite element method (FEM) principle, a 3-dimens ional (3D) rigid-plastic FE simulation system named TBS -3D (tube bending simu lation by 3D FEM) for the NC bending process of thin-walled tube has been devel oped, a reasonable FEM model has been established. By use of this FEM simulation system, a NC bending process of thin-walled has been simulated. And deformed m eshes under different bending stages, stress distribution along bending directio n, relationship between maximal wall thickness changing ratio and bending angle have been obtained. And then some forming laws of NC tube bending obtained are a s follows: (1) NC bending process make tube elongate to some extent; (2) Charact eristic of stress distribution is that the outer area is undergoing tensile stre ss, the inner area is undergoing compression stress, and stress neutral layer mo ves close to the inner area, which is in good accordance with the practice; (3) Maximal wall thinning ratio in the outer tensile area changes only a little with increase of bending angle, and maximal wall thickening ratio in the inner compr ession area increases linearly with bending angle. The above results show that 3 D FE simulation is an important and valid tool of analyzing NC bending process o f tube, this research is beneficial for the practical tube bending process, and it may serve as a significant guide to the practice of the relevant processes.展开更多
Faba bean(Vicia faba L.)has been identified as a rich source of L-DOPA,which is used in treating Parkinson's disease.Biosynthesis and accumulation of active substances such as L-DOPA in plant tissues may interact ...Faba bean(Vicia faba L.)has been identified as a rich source of L-DOPA,which is used in treating Parkinson's disease.Biosynthesis and accumulation of active substances such as L-DOPA in plant tissues may interact with growing conditions and processing methods.Accumulation trends of L-DOPA in various faba bean organs and the effect of drought stress and N fertilization on L-DOPA content were studied in a field and two greenhouse experiments.The influence of various processing methods on L-DOPA content of faba bean tissues was evaluated.The highest L-DOPA content was detected in fresh leaves(22.4 mg g^(-1))followed by flowers,young pods,mature seeds,and roots.Regardless of processing method,L-DOPA concentration in faba bean tissues was significantly reduced when tissues were boiled or dried.Among various methods of processing,freezing had the lowest detrimental effect,reducing L-DOPA concentrations by 24.1%and 21.1%in leaves and seeds,respectively.Drought stress elevated L-DOPA concentration,and maximum L-DOPA(23.3 mg g^(-1)of biomass)was extracted from plants grown under severe drought stress.However,L-DOPA yield(L-DOPA concentration×biomass)was compromised,owing to the adverse influence of drought stress on dry matter production.No significant difference in L-DOPA concentration was detected among various N application rates.展开更多
In order to explore the effect of carbon and nitrogen(C/N)ratio on the performance of anoxic/aerobic-moving bed bio-film reactor(A/O-MBBR)process for treating mariculture wastewater,a laboratory-scale A/O-MBBR was con...In order to explore the effect of carbon and nitrogen(C/N)ratio on the performance of anoxic/aerobic-moving bed bio-film reactor(A/O-MBBR)process for treating mariculture wastewater,a laboratory-scale A/O-MBBR was conducted.The results showed that the reduction of C/N ratio was conducive to improving the removal efficiency of chemical oxygen demand(COD)and ammonia nitrogen(NH_(4)^(+)-N),while inhibiting that of nitrite nitrogen(NO_(2)^(−)-N)and nitrate nitrogen(NO_(3)^(−)-N).The extracellular polymeric substances(EPS)in anoxic zone were significantly higher in concentration than that in aerobic zone although they both declined with decrease of C/N ratio.The result provides solid support for better controlling the pollution of mariculture wastewater.展开更多
The critical nitrogen dilution curve (CNDC) can be used as a diagnostic tool to assess crop N nutrition during the growing season. Potato cultivars have different biomass production and accumulation of N and consequen...The critical nitrogen dilution curve (CNDC) can be used as a diagnostic tool to assess crop N nutrition during the growing season. Potato cultivars have different biomass production and accumulation of N and consequently different growth patterns. These differences among cultivars may result in different CNDC. The aims were a) to determine the CNDC for different potato cultivars;b) to compare these curves with reference curves;and c) to assess the possibility of using the CNDC to estimate the N nutritional status of the crop. The biomass production and N concentration of shoots and tubers of potato cultivars Innovator, Gem Russet, Umatilla Russet, Bannock Russet and Markies Russet were measured. The harvest index (HI) and N harvest index (NHI) were determined. The coefficient a of the CNDC was similar among cultivars, while the coefficients b for Innovator and Gem Russet (-0.42 and -0.36, respectively) were smaller than those for the other cultivars (average -0.25). HI and NHI were greater in Innovator, smaller in Markies Russet, and intermediated in the other three cultivars. The coefficients b of the CNDC were correlated with HI and NHI (HI, r = -0.62, p < 0.0001 and -0.53, p < 0.0001;NHI, r = -0.60, p < 0.0001 and -0.61, p < 0.0001 for 2004/5 and 2005/6, respectively). The relationship between relative tuber yield (RY) and N nutrition index (NNI) was fit by a quadratic-plateau function. At similar situations of N deficiency, Innovator had lower yield and greater response to N rate than the other potato cultivars. The differences in HI and NHI among cultivars may explain the differences in the coefficient b of the CNDC. The NNI identified the status of N adequately in potato cultivars.展开更多
Mn18Cr18N, the high-nitrogen steel, is the 2nd generation material for manufacturing the retaining ring of firepower generators. In this paper, the hot deformation behavior of the material was investigated by thermo-m...Mn18Cr18N, the high-nitrogen steel, is the 2nd generation material for manufacturing the retaining ring of firepower generators. In this paper, the hot deformation behavior of the material was investigated by thermo-mechanical modeling tests. And the flow stress curves of the steel were obtained for various combinations of the temperature and strain rate. Based on the results of the tests, the complex forming process of a retaining ring including punching, expanding and extrusion with an enclosure was put forward and simulated by means of numerical simulation method. The results indicate that the process is a novel and force-saved practical technology for manufacturing heavy retaining rings.展开更多
Semantic processing is a high level cognition function of the human brain. It has been argued intensively whether this process could be accomplished in the absence of awareness. Continuous flash suppression (CFS) is a...Semantic processing is a high level cognition function of the human brain. It has been argued intensively whether this process could be accomplished in the absence of awareness. Continuous flash suppression (CFS) is a powerful approach to create stable unconscious state. In this study, subjects were required to observe a series of paired Chinese words and judge the correlation between them in CFS paradigm. A negative component of event related potential, N400, and a Brain symmetry index were used to measure whether the meaning of the paired stimulus was registered in subliminal semantic processing. Analysis didn’t detect a significant difference in N400 response and EEG signal symmetry between correlated and uncorrelated pairs under unconscious condition. These results support the view that semantic information of Chinese character processing is absent without consciousness created by CFS.展开更多
Adipic acid is an important petrochemical product,and its production process emits a high concentration of greenhouse gas N_2 O.This paper aims to provide quantitative references for relevant authorities to formulate ...Adipic acid is an important petrochemical product,and its production process emits a high concentration of greenhouse gas N_2 O.This paper aims to provide quantitative references for relevant authorities to formulate greenhouse gas control roadmaps.The forecasting method of this paper is consistent with the published national inventory in terms of caliber.Based on the N_2 O abatement technical parameters of adipic acid and the production trend,this paper combines the scenario analysis and provides a measurement of comprehensive N_2 O abatement effect of the entire industry in China.Four future scenarios are assumed.The baseline scenario(BAUS) is a frozen scenario.Three emission abatement scenarios(ANAS,SNAS,and ENAS) are assumed under different strength of abatement driving parameters.The results show that China's adipic acid production process can achieve increasingly significant N_2 O emission abatement effects.Compared to the baseline scenario,by 2030,the N_2 O emission abatements of the three emission abatement scenarios can reach 207-399 kt and the emission abatement ratios can reach 32.5%-62.6%.By 2050,the N_2 O emission abatements for the three emission abatement scenarios can reach 387-540 kt and the emission abatement ratios can reach 71.4%-99.6%.展开更多
Hot deformation behavior of as-cast Mn18Cr18 N austenitic stainless steel was studied in the temperature range of 950-1200 ℃ and strain rate range of 0.001-1 s^(-1) using isothermal hot compression tests. The true ...Hot deformation behavior of as-cast Mn18Cr18 N austenitic stainless steel was studied in the temperature range of 950-1200 ℃ and strain rate range of 0.001-1 s^(-1) using isothermal hot compression tests. The true stress-strain curves of the steel were characterized by hardening and subsequent softening and varied with temperatures and strain rates. The hot deformation activation energy of the steel was calculated to be 657.4 k J/mol, which was higher than that of the corresponding wrought steel due to its as-cast coarse columnar grains and heterogeneous structure. Hot processing maps were developed at different plastic strains, which exhibited two domains with peak power dissipation efficiencies at 1150 ℃/0.001 s^(-1) and 1200 ℃/1 s^(-1), respectively. The corresponding microstructures were analyzed by optical microscopy(OM), scanning electron microscopy(SEM), and electron backscatter diffraction(EBSD). It has been confirmed that dynamic recrystallization(DRX) controlled by dislocation slipping and climbing mechanism occurs in the temperature and strain rate range of 1050-1200 ℃ and 0.001-0.01 s^(-1); And DRX controlled by twinning mechanism occurs in the temperature and strain rate range of 1100-1200 ℃, 0.1-1 s^(-1). These two DRX domains can serve as the hot working windows of the as-cast steel at lower strain rates and at higher strain rates, respectively. The processing maps at different strains also exhibit that the instability region decreases with increasing strain. The corresponding microstructures and the less tensile ductility in the instability region imply that the flow instability is attributed to flow localization accelerated by a few layers of very fine recrystallized grains along the original grain boundaries.展开更多
The transformation process of an m-DOF free-floating robot from one staticstate to a different static state has m degrees of freedom. The proposed approach of thesetransformations utilizes a series of single-DOF trans...The transformation process of an m-DOF free-floating robot from one staticstate to a different static state has m degrees of freedom. The proposed approach of thesetransformations utilizes a series of single-DOF transformation processes as an alternative to them-DOF transformation process. Two static state transformation processes are studied in detail.First, a single-DOF transformation process is established using a newly defined concept, referred toas transformation planning, and the definite integral of conservation of angular momentum. Second,the governing equation of the single-DOF transformation process is established using the dynamicequations of motion of the robot. This allows the joint torques to be computed to effect the statetransformation. Finally, an extension of the single-DOF transformation process is proposed to extendthe application of this proposed transformation methodology to create a transformation net whichallows the reconfiguration of a robot from one state to many other possible states.展开更多
The unreasonable nitrogen(N)supply and low productivity are the main factors restricting the sustainable development of processing tomatoes.In addition,the mechanism by which the N application strategy affects root gr...The unreasonable nitrogen(N)supply and low productivity are the main factors restricting the sustainable development of processing tomatoes.In addition,the mechanism by which the N application strategy affects root growth and nitrate distributions in processing tomatoes remains unclear.In this study,we applied four N application levels to a field(including 0(N0),200(N200),300(N300),and 400(N400)kg/hm^(2))based on the critical N absorption ratio at each growth stage(planting stage to flowering stage:22%;fruit setting stage:24%;red ripening stage:45%;and maturity stage:9%).The results indicated that N300 treatment significantly improved the aboveground dry matter(DM),yield,N uptake,and nitrogen use efficiency(NUE),while N400 treatment increased nitrate nitrogen(NO_(3)^(-)-N)residue in the 20–60 cm soil layer.Temporal variations of total root dry weight(TRDW)and total root length(TRL)showed a single-peak curve.Overall,N300 treatment improved the secondary root parameter of TRDW,while N400 treatment improved the secondary root parameter of TRL.The grey correlation coefficients indicated that root dry weight density(RDWD)in the surface soil(0–20 cm)had the strongest relationship with yield,whereas root length density(RLD)in the middle soil(20–40 cm)had a strong relationship with yield.The path model indicated that N uptake is a crucial factor affecting aboveground DM,TRDW,and yield.The above results indicate that N application levels based on critical N absorption improve the production of processing tomatoes by regulating N uptake and root distribution.Furthermore,the results of this study provide a theoretical basis for precise N management.展开更多
A two-dimensional (2D) fluid model is presented to study the behavior of silicon plasma mixed with SiH4 , N2 , and NH3 in a radio-frequency capacitively coupled plasma (CCP) reactor. The plasma–wall interaction ...A two-dimensional (2D) fluid model is presented to study the behavior of silicon plasma mixed with SiH4 , N2 , and NH3 in a radio-frequency capacitively coupled plasma (CCP) reactor. The plasma–wall interaction (including the deposition) is modeled by using surface reaction coefficients. In the present paper we try to identify, by numerical simulations, the effect of variations of the process parameters on the plasma properties. It is found from our simulations that by increasing the gas pressure and the discharge gap, the electron density profile shape changes continuously from an edge-high to a center-high, thus the thin films become more uniform. Moreover, as the N2 /NH3 ratio increases from 6/13 to 10/9, the hydrogen content can be significantly decreased, without decreasing the electron density significantly.展开更多
The main classical schools of Chinese philosophy can be characterized as process thinking and their concepts are related to those of Whitehead's philosophy of organism. (Neo-)Confucianism, Daoism, and Chinese Buddh...The main classical schools of Chinese philosophy can be characterized as process thinking and their concepts are related to those of Whitehead's philosophy of organism. (Neo-)Confucianism, Daoism, and Chinese Buddhism all find their roots in the Yi ding with a strong emphasis on human experience of the flux of time. These Eastern and Western world views allow attempts to consciously experience experiential reality in terms of immanent transcendence. These attempts are discussed also by considering the functioning of the human brain, emphasizing the importance of brain asymmetry.展开更多
In this brief essay, we will argue that modem neuroscience and Whitehead's process thinking arrive at rather similar conclusions about the essence of human experiences. Important issues evolving from neuroscientific ...In this brief essay, we will argue that modem neuroscience and Whitehead's process thinking arrive at rather similar conclusions about the essence of human experiences. Important issues evolving from neuroscientific research, specifying the identity of human beings, are explained as resulting from the development and stepwise changes of highly dynamic neuronal networks. These conclusions appear to fit the (meta)physical concepts developed by Whitehead, who claims that the elucidation of immediate experience, proceeding from objectivity to subjectivity, is the sole justification of our thought. Both lines of thought assume that our bodily experience, emerging from the perception of various bodily organs, is the basis of our existence.展开更多
A class of N-parameter Gaussian processes are introduced, which are more general than the N-parameter Wiener process. The definition of the set generated by exceptional oscillations of a class of these processes is gi...A class of N-parameter Gaussian processes are introduced, which are more general than the N-parameter Wiener process. The definition of the set generated by exceptional oscillations of a class of these processes is given, and then the Hausdorff dimension of this set is defined. The Hausdorff dimensions of these processes are studied and an exact representative for them is given, which is similar to that for the two-parameter Wiener process by Zacharie (2001). Moreover, the time set considered is a hyperrectangle which is more general than a hyper-scluare used by Zacharie (2001). For this more general case, a Fernique-type inequality is established and then using this inequality and the Slepian lemma, a Levy's continuity modulus theorem is shown. Independence of increments is required for showing the representative of the Hausdorff dimension by Zacharie (2001). This property is absent for the processes introduced here, so we have to find a different way.展开更多
基金Supported by the National Natural Science Foundation of China( No.2 0 0 730 38,2 0 2 330 10 )
文摘The photo-induced electron transfer reactions of anthracene with N,N -diethylaniline(DEA) and phenothiazine(PTZ) occur in the membrane phase of a Triton X-100/ n -C 10 H 21 OH(1-decanol)/H 2O microemulsion. DEA and PTZ exist in the membrane phase of the microemulsion. Anthracene exists in the oil continuous phase of the W/O microemulsion and in the oil core and membrane phase of the O/W microemulsion.
基金supported by the Key Tech-nologies R&D Program of China during the 11th Five-Year Plan period (2006BAD17B02)Central Public Research Institutes Basic Funds for Research and Development (Institute of Agro-Environmental Protection,Ministry of Agriculture), China
文摘A lab-incubation experiment was conducted to investigate the effects of different forms of nitrogen application (ammonium, NH4+-N; nitrate, NO3--N; and amide-N, NH2-N) and different concentrations (40, 200 and 800 mg L-1) on N2O emission from the fluvo-aquic soil subjected to a freezing-thawing cycling. N2O emission sharply decreased at the start of soil freezing, and then showed a smooth line with soil freezing. In subject to soil thawing, N2O emission increased and reached a peak at the initial thawing stage. The average N2O emissions with addition of NH4+-N, NO3 -N and NH2-N are 119.01, 611.61 and 148. 22 ug m-2 h-1, respectively, at the concentration of 40 mg L-1; 205.28, 1 084.40 and 106.13 ug m2 h-1 at the concentration of 200 mg L-1; and 693.95, 1 820.02 and 49.74 ug m-2 h4 at the concentration of 800 mg L-1. The control is only 100.35 ug m-2 h-1. N2O emissions with addition of NH4+-N and NO3--N increased with increasing concentration, by ranging from 17.49 to 425.67% for NH4+-N, and from 563.38 to 1458.6% for NO3--N compared with control. There was a timelag for N2O emission to reach a steady state with an increase of concentration. In contrast, by adding NH2-N to soil, N2O emission decreased with increasing concentration. In sum, NH4+-N or NO3--N fertilizer incorporated in soil enhanced the cumulative N2O emission from the fluvo-aquic soil relative to amide-N. This study suggested that ammonium and nitrate concentration in overwintering water should be less than 200 and 40 mg L-1 in order to reduce N2O emissions from soil, regardless of amide-N.
基金Supported by the National Natural Science Foundation of China.
文摘In this article, authors discuss the problem of uniform packing dimension of the image set of multiparameter stochastic processes without random uniform Holder condition, and obtain the uniform packing dimension of multiparameter stable processes. If Z is a stable (N, d, α)-process and αN ≤ d, then the following holds with probability 1 Dim Z(E)=α Dim E for any Borel setE ∈B(R +^N), where Z(E)={x:E←t∈E,Z(t)=x}, Dim (E) denotes the packing dimension of E.
文摘The numerical control (NC) precision bending process of thin-walled tube is on e of advanced plastic forming processes with high efficiency, forming precision, strength/weight ratio and low cost, thus it is playing more and more important role in manufacturing parts in aerospace and automobile industries. However, the determination of parameters crucial to make sure tube parts qualified is heavil y experience-based and involves repeated trial-and-errors in practice, which makes the production efficiency reduce drastically and does not fulfill the deve lopment of high technology. With quick development of computer technology and gr adual perfect of plastic forming theory, computer numerical simulation based on finite element method (FEM) has become one of important tools of researching and developing plastic forming technology. Development trend of NC precision bendin g process of tube is simulating its forming process by FEM. Because NC tube bend ing is of 3D nature, it is of great importance to analyze the forming mechanism and find out the influence law of forming parameters on forming process in the N C precision bending process of thin-walled tube quantitatively by 3D FE simulat ion. Based on the rigid-plastic finite element method (FEM) principle, a 3-dimens ional (3D) rigid-plastic FE simulation system named TBS -3D (tube bending simu lation by 3D FEM) for the NC bending process of thin-walled tube has been devel oped, a reasonable FEM model has been established. By use of this FEM simulation system, a NC bending process of thin-walled has been simulated. And deformed m eshes under different bending stages, stress distribution along bending directio n, relationship between maximal wall thickness changing ratio and bending angle have been obtained. And then some forming laws of NC tube bending obtained are a s follows: (1) NC bending process make tube elongate to some extent; (2) Charact eristic of stress distribution is that the outer area is undergoing tensile stre ss, the inner area is undergoing compression stress, and stress neutral layer mo ves close to the inner area, which is in good accordance with the practice; (3) Maximal wall thinning ratio in the outer tensile area changes only a little with increase of bending angle, and maximal wall thickening ratio in the inner compr ession area increases linearly with bending angle. The above results show that 3 D FE simulation is an important and valid tool of analyzing NC bending process o f tube, this research is beneficial for the practical tube bending process, and it may serve as a significant guide to the practice of the relevant processes.
基金partially funded through a graduate student grant received from Northeast Sustainable Agriculture Research and Education(GNE14-078)
文摘Faba bean(Vicia faba L.)has been identified as a rich source of L-DOPA,which is used in treating Parkinson's disease.Biosynthesis and accumulation of active substances such as L-DOPA in plant tissues may interact with growing conditions and processing methods.Accumulation trends of L-DOPA in various faba bean organs and the effect of drought stress and N fertilization on L-DOPA content were studied in a field and two greenhouse experiments.The influence of various processing methods on L-DOPA content of faba bean tissues was evaluated.The highest L-DOPA content was detected in fresh leaves(22.4 mg g^(-1))followed by flowers,young pods,mature seeds,and roots.Regardless of processing method,L-DOPA concentration in faba bean tissues was significantly reduced when tissues were boiled or dried.Among various methods of processing,freezing had the lowest detrimental effect,reducing L-DOPA concentrations by 24.1%and 21.1%in leaves and seeds,respectively.Drought stress elevated L-DOPA concentration,and maximum L-DOPA(23.3 mg g^(-1)of biomass)was extracted from plants grown under severe drought stress.However,L-DOPA yield(L-DOPA concentration×biomass)was compromised,owing to the adverse influence of drought stress on dry matter production.No significant difference in L-DOPA concentration was detected among various N application rates.
基金This work was supported by the National Key Research and Development Program of China(No.2018 YFC1407601)the Start-up Foundation for Introducing Talent of NUIST and Guangxi Innovation Driven Development Project(major science and technology project).
文摘In order to explore the effect of carbon and nitrogen(C/N)ratio on the performance of anoxic/aerobic-moving bed bio-film reactor(A/O-MBBR)process for treating mariculture wastewater,a laboratory-scale A/O-MBBR was conducted.The results showed that the reduction of C/N ratio was conducive to improving the removal efficiency of chemical oxygen demand(COD)and ammonia nitrogen(NH_(4)^(+)-N),while inhibiting that of nitrite nitrogen(NO_(2)^(−)-N)and nitrate nitrogen(NO_(3)^(−)-N).The extracellular polymeric substances(EPS)in anoxic zone were significantly higher in concentration than that in aerobic zone although they both declined with decrease of C/N ratio.The result provides solid support for better controlling the pollution of mariculture wastewater.
文摘The critical nitrogen dilution curve (CNDC) can be used as a diagnostic tool to assess crop N nutrition during the growing season. Potato cultivars have different biomass production and accumulation of N and consequently different growth patterns. These differences among cultivars may result in different CNDC. The aims were a) to determine the CNDC for different potato cultivars;b) to compare these curves with reference curves;and c) to assess the possibility of using the CNDC to estimate the N nutritional status of the crop. The biomass production and N concentration of shoots and tubers of potato cultivars Innovator, Gem Russet, Umatilla Russet, Bannock Russet and Markies Russet were measured. The harvest index (HI) and N harvest index (NHI) were determined. The coefficient a of the CNDC was similar among cultivars, while the coefficients b for Innovator and Gem Russet (-0.42 and -0.36, respectively) were smaller than those for the other cultivars (average -0.25). HI and NHI were greater in Innovator, smaller in Markies Russet, and intermediated in the other three cultivars. The coefficients b of the CNDC were correlated with HI and NHI (HI, r = -0.62, p < 0.0001 and -0.53, p < 0.0001;NHI, r = -0.60, p < 0.0001 and -0.61, p < 0.0001 for 2004/5 and 2005/6, respectively). The relationship between relative tuber yield (RY) and N nutrition index (NNI) was fit by a quadratic-plateau function. At similar situations of N deficiency, Innovator had lower yield and greater response to N rate than the other potato cultivars. The differences in HI and NHI among cultivars may explain the differences in the coefficient b of the CNDC. The NNI identified the status of N adequately in potato cultivars.
文摘Mn18Cr18N, the high-nitrogen steel, is the 2nd generation material for manufacturing the retaining ring of firepower generators. In this paper, the hot deformation behavior of the material was investigated by thermo-mechanical modeling tests. And the flow stress curves of the steel were obtained for various combinations of the temperature and strain rate. Based on the results of the tests, the complex forming process of a retaining ring including punching, expanding and extrusion with an enclosure was put forward and simulated by means of numerical simulation method. The results indicate that the process is a novel and force-saved practical technology for manufacturing heavy retaining rings.
文摘Semantic processing is a high level cognition function of the human brain. It has been argued intensively whether this process could be accomplished in the absence of awareness. Continuous flash suppression (CFS) is a powerful approach to create stable unconscious state. In this study, subjects were required to observe a series of paired Chinese words and judge the correlation between them in CFS paradigm. A negative component of event related potential, N400, and a Brain symmetry index were used to measure whether the meaning of the paired stimulus was registered in subliminal semantic processing. Analysis didn’t detect a significant difference in N400 response and EEG signal symmetry between correlated and uncorrelated pairs under unconscious condition. These results support the view that semantic information of Chinese character processing is absent without consciousness created by CFS.
基金financial support by the Ministry of Science and Technology of China (Grant No.2018YFC1509006)the National Natural Science Foundation of China (Grant No.71874096)+1 种基金the Macao SAR Government Higher Education Fundthe Macao University of Science and Technology (Grant No.FRG-19-008-MSB)。
文摘Adipic acid is an important petrochemical product,and its production process emits a high concentration of greenhouse gas N_2 O.This paper aims to provide quantitative references for relevant authorities to formulate greenhouse gas control roadmaps.The forecasting method of this paper is consistent with the published national inventory in terms of caliber.Based on the N_2 O abatement technical parameters of adipic acid and the production trend,this paper combines the scenario analysis and provides a measurement of comprehensive N_2 O abatement effect of the entire industry in China.Four future scenarios are assumed.The baseline scenario(BAUS) is a frozen scenario.Three emission abatement scenarios(ANAS,SNAS,and ENAS) are assumed under different strength of abatement driving parameters.The results show that China's adipic acid production process can achieve increasingly significant N_2 O emission abatement effects.Compared to the baseline scenario,by 2030,the N_2 O emission abatements of the three emission abatement scenarios can reach 207-399 kt and the emission abatement ratios can reach 32.5%-62.6%.By 2050,the N_2 O emission abatements for the three emission abatement scenarios can reach 387-540 kt and the emission abatement ratios can reach 71.4%-99.6%.
基金Funded by the National Natural Science Foundation of China(No.51575372)
文摘Hot deformation behavior of as-cast Mn18Cr18 N austenitic stainless steel was studied in the temperature range of 950-1200 ℃ and strain rate range of 0.001-1 s^(-1) using isothermal hot compression tests. The true stress-strain curves of the steel were characterized by hardening and subsequent softening and varied with temperatures and strain rates. The hot deformation activation energy of the steel was calculated to be 657.4 k J/mol, which was higher than that of the corresponding wrought steel due to its as-cast coarse columnar grains and heterogeneous structure. Hot processing maps were developed at different plastic strains, which exhibited two domains with peak power dissipation efficiencies at 1150 ℃/0.001 s^(-1) and 1200 ℃/1 s^(-1), respectively. The corresponding microstructures were analyzed by optical microscopy(OM), scanning electron microscopy(SEM), and electron backscatter diffraction(EBSD). It has been confirmed that dynamic recrystallization(DRX) controlled by dislocation slipping and climbing mechanism occurs in the temperature and strain rate range of 1050-1200 ℃ and 0.001-0.01 s^(-1); And DRX controlled by twinning mechanism occurs in the temperature and strain rate range of 1100-1200 ℃, 0.1-1 s^(-1). These two DRX domains can serve as the hot working windows of the as-cast steel at lower strain rates and at higher strain rates, respectively. The processing maps at different strains also exhibit that the instability region decreases with increasing strain. The corresponding microstructures and the less tensile ductility in the instability region imply that the flow instability is attributed to flow localization accelerated by a few layers of very fine recrystallized grains along the original grain boundaries.
文摘The transformation process of an m-DOF free-floating robot from one staticstate to a different static state has m degrees of freedom. The proposed approach of thesetransformations utilizes a series of single-DOF transformation processes as an alternative to them-DOF transformation process. Two static state transformation processes are studied in detail.First, a single-DOF transformation process is established using a newly defined concept, referred toas transformation planning, and the definite integral of conservation of angular momentum. Second,the governing equation of the single-DOF transformation process is established using the dynamicequations of motion of the robot. This allows the joint torques to be computed to effect the statetransformation. Finally, an extension of the single-DOF transformation process is proposed to extendthe application of this proposed transformation methodology to create a transformation net whichallows the reconfiguration of a robot from one state to many other possible states.
基金supported by the National Natural Science Foundation of China (42077011).
文摘The unreasonable nitrogen(N)supply and low productivity are the main factors restricting the sustainable development of processing tomatoes.In addition,the mechanism by which the N application strategy affects root growth and nitrate distributions in processing tomatoes remains unclear.In this study,we applied four N application levels to a field(including 0(N0),200(N200),300(N300),and 400(N400)kg/hm^(2))based on the critical N absorption ratio at each growth stage(planting stage to flowering stage:22%;fruit setting stage:24%;red ripening stage:45%;and maturity stage:9%).The results indicated that N300 treatment significantly improved the aboveground dry matter(DM),yield,N uptake,and nitrogen use efficiency(NUE),while N400 treatment increased nitrate nitrogen(NO_(3)^(-)-N)residue in the 20–60 cm soil layer.Temporal variations of total root dry weight(TRDW)and total root length(TRL)showed a single-peak curve.Overall,N300 treatment improved the secondary root parameter of TRDW,while N400 treatment improved the secondary root parameter of TRL.The grey correlation coefficients indicated that root dry weight density(RDWD)in the surface soil(0–20 cm)had the strongest relationship with yield,whereas root length density(RLD)in the middle soil(20–40 cm)had a strong relationship with yield.The path model indicated that N uptake is a crucial factor affecting aboveground DM,TRDW,and yield.The above results indicate that N application levels based on critical N absorption improve the production of processing tomatoes by regulating N uptake and root distribution.Furthermore,the results of this study provide a theoretical basis for precise N management.
基金Project supported by the China Postdoctoral Science Foundation (Grant No. 2012M511603)the National Natural Science Foundation of China (Grant Nos. 11105057 and 10775025)+1 种基金the Natural Science Foundation of Hubei Province of China (Grant No. 2007ABA035)the Program for New Century Excellent Talents in University of China (Grant No. NCET-08-0073)
文摘A two-dimensional (2D) fluid model is presented to study the behavior of silicon plasma mixed with SiH4 , N2 , and NH3 in a radio-frequency capacitively coupled plasma (CCP) reactor. The plasma–wall interaction (including the deposition) is modeled by using surface reaction coefficients. In the present paper we try to identify, by numerical simulations, the effect of variations of the process parameters on the plasma properties. It is found from our simulations that by increasing the gas pressure and the discharge gap, the electron density profile shape changes continuously from an edge-high to a center-high, thus the thin films become more uniform. Moreover, as the N2 /NH3 ratio increases from 6/13 to 10/9, the hydrogen content can be significantly decreased, without decreasing the electron density significantly.
文摘The main classical schools of Chinese philosophy can be characterized as process thinking and their concepts are related to those of Whitehead's philosophy of organism. (Neo-)Confucianism, Daoism, and Chinese Buddhism all find their roots in the Yi ding with a strong emphasis on human experience of the flux of time. These Eastern and Western world views allow attempts to consciously experience experiential reality in terms of immanent transcendence. These attempts are discussed also by considering the functioning of the human brain, emphasizing the importance of brain asymmetry.
文摘In this brief essay, we will argue that modem neuroscience and Whitehead's process thinking arrive at rather similar conclusions about the essence of human experiences. Important issues evolving from neuroscientific research, specifying the identity of human beings, are explained as resulting from the development and stepwise changes of highly dynamic neuronal networks. These conclusions appear to fit the (meta)physical concepts developed by Whitehead, who claims that the elucidation of immediate experience, proceeding from objectivity to subjectivity, is the sole justification of our thought. Both lines of thought assume that our bodily experience, emerging from the perception of various bodily organs, is the basis of our existence.
基金Project supported by the National Natural Science Foundation of China(No.10571159)the Doctoral Foundation of Ministry of Education of China(No.20060335032)
文摘A class of N-parameter Gaussian processes are introduced, which are more general than the N-parameter Wiener process. The definition of the set generated by exceptional oscillations of a class of these processes is given, and then the Hausdorff dimension of this set is defined. The Hausdorff dimensions of these processes are studied and an exact representative for them is given, which is similar to that for the two-parameter Wiener process by Zacharie (2001). Moreover, the time set considered is a hyperrectangle which is more general than a hyper-scluare used by Zacharie (2001). For this more general case, a Fernique-type inequality is established and then using this inequality and the Slepian lemma, a Levy's continuity modulus theorem is shown. Independence of increments is required for showing the representative of the Hausdorff dimension by Zacharie (2001). This property is absent for the processes introduced here, so we have to find a different way.