Paddy fields contaminated with cadmium(Cd)present decreased grain yield and produce Cckcontaminated grains.Screening for low-Cd-accumulating cultivars is a useful method to reduce the amount of Cd in the grains.The pr...Paddy fields contaminated with cadmium(Cd)present decreased grain yield and produce Cckcontaminated grains.Screening for low-Cd-accumulating cultivars is a useful method to reduce the amount of Cd in the grains.The present study aimed to examine the roles of the root morphology and an atomy in Cd tran slocati on and accumulati on in rice plants.Twenty・two rice cultivars were used in the first experiment,after which two cultivars[Zixiangnuo(ZXN)and Jinyou T36(JYT36)]were selected and used in subsequent experiments under hydroponic conditions.The results showed that there were significant differences in Cd concentrations in the shoots(ranging from 4 to 100 mg/kg)and the Cd translocation rates(shoot/root)(from 7%to 102%)among the 22 cultivars,and the shoot Cd concentration was significantly correlated with the Cd translocation rate of the 22 cultivars under 0.1 mg/L Cd treatment.Compared with cultivar ZXN,JYT36 had greater root Cd uptake and accumulation but lower shoot Cd accumulation and Cd translocation rate.The number of root tips per surface area of cultivar ZXN was greater than that of JYT36,while the average root diameter was lower than that of JYT36.Compared with ZXN,JYT36 had stronger apoplastic barriers,and the Casparian bands and suberin lamellae in the root endodermis and exodermis were closer to the root apex in both the control and Cd treatments,especially for suberin lamellae in the root exodermis with Cd treatments,with a differenee of 25 mm.The results also showed that,compared with ZXN,JYT36 had greater percentages of Cd bound in cell walls and intracellular Cd but lower Cd concentrations in the apoplastic fluid under the Cd treatment.The results suggested that Cd translocation,rather than root Cd uptake,is a key process that determi nes Cd accumulati on in the rice shoots.The root morphological and an atomical characteristics evidently affect Cd accumulation in the shoots by inhibiting Cd translocation,especially via the apoplastic pathway.It was possible to pre-screen low・Cd・accumulating rice cultivars on the basis of their root morphology,an atomical characteristics and Cd tran slocati on rate at the seedling stage.展开更多
Recently, one of the authors and his coworkers made a study of the electron structure of Layered Ultrathin Coherent Structures (LUCS) in the tight binding approximation. We now present an alternative formalism in term...Recently, one of the authors and his coworkers made a study of the electron structure of Layered Ultrathin Coherent Structures (LUCS) in the tight binding approximation. We now present an alternative formalism in terms of real space Green’s functions which is suited to the investigation of the electron as well as of展开更多
It is well known that if f(z) belongs to Hardy space H^P in the upper plane, where 1≤p≤∞, then f(x+iy) is the Poisson integral of the corresponding boundary function on real axis. And the Paley-Wiener theorem was p...It is well known that if f(z) belongs to Hardy space H^P in the upper plane, where 1≤p≤∞, then f(x+iy) is the Poisson integral of the corresponding boundary function on real axis. And the Paley-Wiener theorem was proved for 1≤p≤2. The situation becomes different in the ease 0<p<1, since the Poisson integral formula is not established when the boundary value is taken by a function of L^P (0<p<1), which is defined almost everywhere on real axis. The classical argument of the proof of Paley-Wiener theorem does not seem quite appli-展开更多
An enrichment factor as large as possible and a height equivalent to theoretical plate (HETP) as small as possible are required in isotope enrichments. The relation between enrichment factor, HETP and degree of enrich...An enrichment factor as large as possible and a height equivalent to theoretical plate (HETP) as small as possible are required in isotope enrichments. The relation between enrichment factor, HETP and degree of enrichment can be expressed by the boundary equation of the equilibrium theory of the distillation type展开更多
Let （X1, θ1）,…, （Xn, θn） be iid. samples, usually called training samples from the population （X,θ） which is an Rd×（1, 2, …, s）-valued random vector, and let ρ be a distance function equivalent to t...Let （X1, θ1）,…, （Xn, θn） be iid. samples, usually called training samples from the population （X,θ） which is an Rd×（1, 2, …, s）-valued random vector, and let ρ be a distance function equivalent to the Euclidean one in Rd. For X = x, rank the （Xj, θj）, j = 1,2,…,n, according to increasing values of ρ（Xj, x） (ties are broken展开更多
Benzoylferrocene is an organometallic compound of red crystal with the formula C17H14FeO, M. W. 290, m. p. 108℃. The crystal is monoclinic, with space group P21/n and crystal data: a=13.904（3）, b=15.222（3）, c=6....Benzoylferrocene is an organometallic compound of red crystal with the formula C17H14FeO, M. W. 290, m. p. 108℃. The crystal is monoclinic, with space group P21/n and crystal data: a=13.904（3）, b=15.222（3）, c=6.201（1）（?）, β=99°24′, V=1295.4（?）,Dobs.=1.47g·cm-3, Dcalc.=1.47g·cm-3, Z=4, F000=600. Three-dimensional X-ray diffraction data were collected in the range of展开更多
SiC is known to form many polytypes with different stackings of close-packed layers among which 4H, 15R, 6H and 21R are the polytypes most frequently occurring. Up to the present of the more than one hundred polytypes...SiC is known to form many polytypes with different stackings of close-packed layers among which 4H, 15R, 6H and 21R are the polytypes most frequently occurring. Up to the present of the more than one hundred polytypes known many have been found belonging to the [（3, 3）n （3, 2）]8 and [（3, 3）n （3, 4）]8 families. They could be considered as structures derived from the （3, 3） stacking sequence of the 6H poly-展开更多
基金supported by the National Key Research and Development Program of China(Grant No.2018YFD0800700)the National Natural Science Foundation of China(Grant No.31670409)+1 种基金the General Research Fund Proposal of Hong Kong,China(Grant No.RG21/2020-2021R)the Faculty of Liberal Arts and Social Sciences of the Education University of Hong Kong,China(Grant No.04548(IRS-10)).
文摘Paddy fields contaminated with cadmium(Cd)present decreased grain yield and produce Cckcontaminated grains.Screening for low-Cd-accumulating cultivars is a useful method to reduce the amount of Cd in the grains.The present study aimed to examine the roles of the root morphology and an atomy in Cd tran slocati on and accumulati on in rice plants.Twenty・two rice cultivars were used in the first experiment,after which two cultivars[Zixiangnuo(ZXN)and Jinyou T36(JYT36)]were selected and used in subsequent experiments under hydroponic conditions.The results showed that there were significant differences in Cd concentrations in the shoots(ranging from 4 to 100 mg/kg)and the Cd translocation rates(shoot/root)(from 7%to 102%)among the 22 cultivars,and the shoot Cd concentration was significantly correlated with the Cd translocation rate of the 22 cultivars under 0.1 mg/L Cd treatment.Compared with cultivar ZXN,JYT36 had greater root Cd uptake and accumulation but lower shoot Cd accumulation and Cd translocation rate.The number of root tips per surface area of cultivar ZXN was greater than that of JYT36,while the average root diameter was lower than that of JYT36.Compared with ZXN,JYT36 had stronger apoplastic barriers,and the Casparian bands and suberin lamellae in the root endodermis and exodermis were closer to the root apex in both the control and Cd treatments,especially for suberin lamellae in the root exodermis with Cd treatments,with a differenee of 25 mm.The results also showed that,compared with ZXN,JYT36 had greater percentages of Cd bound in cell walls and intracellular Cd but lower Cd concentrations in the apoplastic fluid under the Cd treatment.The results suggested that Cd translocation,rather than root Cd uptake,is a key process that determi nes Cd accumulati on in the rice shoots.The root morphological and an atomical characteristics evidently affect Cd accumulation in the shoots by inhibiting Cd translocation,especially via the apoplastic pathway.It was possible to pre-screen low・Cd・accumulating rice cultivars on the basis of their root morphology,an atomical characteristics and Cd tran slocati on rate at the seedling stage.
文摘Recently, one of the authors and his coworkers made a study of the electron structure of Layered Ultrathin Coherent Structures (LUCS) in the tight binding approximation. We now present an alternative formalism in terms of real space Green’s functions which is suited to the investigation of the electron as well as of
文摘It is well known that if f(z) belongs to Hardy space H^P in the upper plane, where 1≤p≤∞, then f(x+iy) is the Poisson integral of the corresponding boundary function on real axis. And the Paley-Wiener theorem was proved for 1≤p≤2. The situation becomes different in the ease 0<p<1, since the Poisson integral formula is not established when the boundary value is taken by a function of L^P (0<p<1), which is defined almost everywhere on real axis. The classical argument of the proof of Paley-Wiener theorem does not seem quite appli-
文摘An enrichment factor as large as possible and a height equivalent to theoretical plate (HETP) as small as possible are required in isotope enrichments. The relation between enrichment factor, HETP and degree of enrichment can be expressed by the boundary equation of the equilibrium theory of the distillation type
文摘Let （X1, θ1）,…, （Xn, θn） be iid. samples, usually called training samples from the population （X,θ） which is an Rd×（1, 2, …, s）-valued random vector, and let ρ be a distance function equivalent to the Euclidean one in Rd. For X = x, rank the （Xj, θj）, j = 1,2,…,n, according to increasing values of ρ（Xj, x） (ties are broken
文摘Benzoylferrocene is an organometallic compound of red crystal with the formula C17H14FeO, M. W. 290, m. p. 108℃. The crystal is monoclinic, with space group P21/n and crystal data: a=13.904（3）, b=15.222（3）, c=6.201（1）（?）, β=99°24′, V=1295.4（?）,Dobs.=1.47g·cm-3, Dcalc.=1.47g·cm-3, Z=4, F000=600. Three-dimensional X-ray diffraction data were collected in the range of
文摘SiC is known to form many polytypes with different stackings of close-packed layers among which 4H, 15R, 6H and 21R are the polytypes most frequently occurring. Up to the present of the more than one hundred polytypes known many have been found belonging to the [（3, 3）n （3, 2）]8 and [（3, 3）n （3, 4）]8 families. They could be considered as structures derived from the （3, 3） stacking sequence of the 6H poly-
