E-learning platforms support education systems worldwide, transferring theoretical knowledge as well as soft skills. In the present study high-school pupils’, and adult students’ opinions were evaluated through a mo...E-learning platforms support education systems worldwide, transferring theoretical knowledge as well as soft skills. In the present study high-school pupils’, and adult students’ opinions were evaluated through a modern structured MOODLE interactive course, designed for the needs of the laboratory course “Automotive Systems”. The study concerns Greek secondary vocational education pupils aged 18 and vocational training adult students aged 20 to 50 years. The multistage, equal size simple random cluster sample was used as a sampling method. Pupils and adult students of each cluster completed structured 10-question questionnaires both before and after attending the course. A total of 120 questionnaires were collected. In general, our findings disclosed that the majority of pupils and adult students had significantly improved their knowledge and skills from using MOODLE. They reported strengthening conventional teaching, using the new MOODLE technology. The satisfaction indices improved quite, with the differences in their mean values being statistically significant.展开更多
Based on the multiplicity results of Benci and Fortunato [4], we consider some elliptic systems with strongly indefinite quadratic part, and establish the existence of infinitely many nontrivial solutions in a suitabl...Based on the multiplicity results of Benci and Fortunato [4], we consider some elliptic systems with strongly indefinite quadratic part, and establish the existence of infinitely many nontrivial solutions in a suitable family of products of fractional Sobolev spaces.展开更多
The basic concepts about the active structures and some attributes of the modes were presented in paper “Liner Active Structures and Modes]( I) ". The characteristics of the active discrete systems and active be...The basic concepts about the active structures and some attributes of the modes were presented in paper “Liner Active Structures and Modes]( I) ". The characteristics of the active discrete systems and active beams were discussed, especially, the stability of the active structures and the orthogonality of the eigenvectors. The notes about modes were portrayed by a model of a seven-storeyed building with sensors and actuators. The concept of the adjoint active structure was extended from the discrete systems to the beams that were the representations of the continuous structures. Two types of beams with different placements of the measuring and actuating systems were discussed in detail. One is the beam with the discrete sensors and actuators, and the other is the beam with distributed sensor and actuator function. The orthogonality conditions were derived with the modal shapes of the active beam and its adjoint active beam. An example shows that the variation of eigenvalues with feedback amplitude for the homo-configuration and non-homo-configuration active structures.展开更多
The samples of the C-S-H series were synthesized by hydrothermal reaction of fumed silica, CaO and deionized water at initial C/S ratios between 1.0-1.7. Phase composition and structural and morphology characteristics...The samples of the C-S-H series were synthesized by hydrothermal reaction of fumed silica, CaO and deionized water at initial C/S ratios between 1.0-1.7. Phase composition and structural and morphology characteristics of C-S-H samples were analyzed by XRD, IR and SEM. The experimental results showed that the d-spacing of (002), (110) and (020) decreased, the d-spacing of (200) increased, and the d-spacing of (310) varied randomly, the polymerization of silica tetrahedra of C-S-H decreased, and morphology of C-S-H samples varied from sheet shapes to long reticular fibers as C/S ratio increased.展开更多
According to specifications for Welding Procedure Qualification of ASME IX Section and Chinese code, JB 4708 2000, a software package for managing welding documents has been rebuilt. Consequently, the new software pa...According to specifications for Welding Procedure Qualification of ASME IX Section and Chinese code, JB 4708 2000, a software package for managing welding documents has been rebuilt. Consequently, the new software package can be used in a Limited Area Network (LAN) with 4 different levels of authorities for different users. Therefore, the welding documents, including DWPS (Design for Welding Procedure Specifications), PQRs (Procedure Qualification Records) and WPS (Welding Procedure Specifications) can be shared within a company. At the same time, the system provides users various functions such as browsing, copying, editing, searching and printing records, and helps users to make decision of whether a new PQR test is necessary or not according to the codes above as well. Furthermore, super users can also browse the history of record modification and retrieve the records when needed.展开更多
The effects of polyaerylamide (PAM) and polyvinyl alcohol (PVA) on morphology and structure of calcium silica~ hydrate with C/S 1.0-1.7 prepared via precipitation in solution were investigated by XRD, FT-IR and TE...The effects of polyaerylamide (PAM) and polyvinyl alcohol (PVA) on morphology and structure of calcium silica~ hydrate with C/S 1.0-1.7 prepared via precipitation in solution were investigated by XRD, FT-IR and TEM techniques. The results show that incorporation of the polymers decreased the order degree, increased the interlayer spacing and disturbed the layered stacking of C-S-H. Interlayer spacing expansion depended on C/S ratios and type of polymer. Interlayer spacing expansion had a minimum at C/S 1.0 and a maximum at C/S 1.3 and 1.5. Interlayer spacing expansion of PAM was bigger than that of PVA with the same C/S. C-S-H added with PVA mainly exhibited foil-like and fibrillar morphology. The fibrils were of variable length from a few tens of nanometers to a few hundreds of nanometers. Fibrils or foils seemed to be longer in the presence of PVA.展开更多
Impurity formation energy, electronic structure, and photocatalytic properties of C-, N-, or S-doped BiOCl are investigated by density-functional theory plus U calculations(DFT + U). Results show that the doping effec...Impurity formation energy, electronic structure, and photocatalytic properties of C-, N-, or S-doped BiOCl are investigated by density-functional theory plus U calculations(DFT + U). Results show that the doping effect of S is better than that of C or N on the tunable photocatalytic activities of BiOCl. At low concentration, S-doped BiOCl systems are the most stable under Bi-rich growth conditions because of their lower impurity-formation energy. Compared with the electronic structures of S-doped BiOCl, C-or N-doped BiOCl have relatively deeper impurity energy levels appearing in their band gap(except Bi_(36)O_(35)NCl_(36)), which may act as photogenerated carrier-recombination centers and reduce photocatalytic activity. At high concentration, S is substituted on the O lattice site system, whereas some S 3p states mix with the valence band; this mixture leads to an obvious band-gap decrease and continuum-state formation above the valence-band edge of BiOCl. Such activity is advantageous to photochemical catalysis response. Compared with pure Bi OCl and a low-concentration S-doped system, a high-concentration S-doped system shows an obvious redshift on the absorption edge and has better photocatalytic O_2 evolution performance.展开更多
(PPh_3)_2Ni(i-mnt),(i-mnt=S_2C=C(CN)_2),Mr=613.43,monoclinic,Pn,a=9.167(3),b=10.872(3), c=18.209(7) ,β=101.46(3)°,V=1779(1) ,Z=2,Dc=1.15 g/cm^3,λ(Moka)=0.71069 ,μ=7.67 cm^(-1), F(000)=648,T=296K,final R=0.060,...(PPh_3)_2Ni(i-mnt),(i-mnt=S_2C=C(CN)_2),Mr=613.43,monoclinic,Pn,a=9.167(3),b=10.872(3), c=18.209(7) ,β=101.46(3)°,V=1779(1) ,Z=2,Dc=1.15 g/cm^3,λ(Moka)=0.71069 ,μ=7.67 cm^(-1), F(000)=648,T=296K,final R=0.060,Rw=0.073 for 1909 observed reflections with Ⅰ≥3σ(Ⅰ).The complex adopts a square planar geometry as its coordination unit,the mean Ni-S and Ni-P distances are 2.216 and 2.221 ,respectivety.展开更多
In the paper, dicalcium silicate (C2S) was modified to obtain higher performance, and the solutionizing pattern of BaSO4 in cement clinker was analyzed theoretically. According to experimental results, solutionizing o...In the paper, dicalcium silicate (C2S) was modified to obtain higher performance, and the solutionizing pattern of BaSO4 in cement clinker was analyzed theoretically. According to experimental results, solutionizing of BaSO4in cement clinker improved crystal plane distance of C2S as well as the relations of coordination. The performance tests show that the strength of C2S modified by BaSO4 changes and the reactivity of C2S increases significantly.展开更多
BACKGROUND Systemic lupus erythematosus(SLE)is an autoimmune disease characterized by systemic involvement and multiple autoantibodies in the serum.Patients with protein C(PC)and protein S(PS)deficiency are prone to t...BACKGROUND Systemic lupus erythematosus(SLE)is an autoimmune disease characterized by systemic involvement and multiple autoantibodies in the serum.Patients with protein C(PC)and protein S(PS)deficiency are prone to thrombosis.In contrast,patients with primary hyperfibrino-lysis tend to bleed.CASE SUMMARY A 52-year-old female patient with bilateral pleural effusion was diagnosed with"tuberculous pleurisy"and treated with anti-tuberculosis drugs and prednisone.The coagulation-related laboratory results showed decreased fibrinogen,PC activity,PS activity,and antithrombinШactivity.The immune-related laboratory results showed positive antinuclear antibody,anti-Smith antibody,anticardiolipin antibody(ACL),anti-β2-glycoprotein I antibody(aβ2GPI)and direct Coomb’s test and decreased complement 3 and complement 4.Thoracoscopy was performed and bloody pleural fluid was drained.Pathology of the pleural biopsy showed lymphocytes,plasma cells,and a few eosinophils in adipose and fibrous connective tissue.Results of whole exome sequencing of blood showed no genetic mutations suggesting the presence of hereditary hematological diseases.The patient was finally diagnosed with SLE and primary hyperfibrinolysis,and was treated with prednisolone,hydroxychloroquine,and compound cyclophosphamide.CONCLUSION PC and PS deficiency in SLE might be related to ACL and aβ2GPI.SLE and primary hyperfibrinolysis can coexist in one patient,with both a risk of thrombosis and a risk of bleeding.展开更多
This paper aimed at studying the effect of different types of soil tillage systems on the change of total carbon (C) and nitrogen (N) in the soil structural units of different size after dry structural analysis of...This paper aimed at studying the effect of different types of soil tillage systems on the change of total carbon (C) and nitrogen (N) in the soil structural units of different size after dry structural analysis of soil. The research was carried out in a 6-field rotation system (grain maize-wheat-sunflower-wheat-bean-wheat) at the end of the 2nd rotation. Six out of 24 soil tillage systems were selected; they were applied independently and in combination in the crop rotation. After that, they were compared to the system with constant deep plowing. So a total of seven soil tillage systems were investigated. The selected systems for main soil tillage were the following: plowing (control variant), disking, cutting, nil tillage (direct sowing), plowing-disking, plowing-nil tillage, disking-nil tillage. Three depths of 0-10, 10-20 and 20-30 cm were studied, as well as soil structural units were of the following sizes: 〉 10 mm, 10-5, 5-3, 3-1, 1-0.25 mm and 〈 0.25 mm. As a result of systematic implementation of different soil tillage systems, higher N and C concentrations were established by the layers according to constant plowing. Constant disking and its alternation with nil tillage increased the total N concentration with 15.6% and 11.1%, respectively, in comparison with the constant plowing. The same was valid for C concentration in soil, but the highest increase was established in the variants with constant cutting and nil tillage. The exceeding was with 14.0% and 13.2%, in comparison to constant plowing. The redistribution of N and C depending on the structural soil units was most expressed in the 0-10 cm and 10-20 cm layers. The highest amounts of C and N were found in the soil units with size less than 5 mm, mainly in the 〈 0.25 mm fraction. At depth of 20-30 cm, the role of the size of soil structural units for C and N redistribution decreased strongly. The values of C/N ratio were moderate only under the use of constant disking. This index was low under all other soil tillage systems. The correlation of total N with C in soil was high, positive and significant depending on the size of structural soil units and the tillage systems, as average for the investigated factors in this experiment. The minimal tillage and the tillage without turning of soil, used independently and in combination, had the highest contribution to preserving the organic matter in the haplic Chernozems of Dobrudzha region.展开更多
(CH_3C_5H_4)Zr(S_2CNBz_2)_3, Mr=987.55, space group P1, a=13.002(4), b=13.659(3), c=29.685(8); α=100.72(2)~o,β=97.23(2)~o, γ=105.36(2)~o; V=4909(2)~3, Z=4, Dc=1.34gcm^(-3), Mo-K(λ=0.71073A) radiation, μ=5.0cm^(-1...(CH_3C_5H_4)Zr(S_2CNBz_2)_3, Mr=987.55, space group P1, a=13.002(4), b=13.659(3), c=29.685(8); α=100.72(2)~o,β=97.23(2)~o, γ=105.36(2)~o; V=4909(2)~3, Z=4, Dc=1.34gcm^(-3), Mo-K(λ=0.71073A) radiation, μ=5.0cm^(-1), R=0.069, Rw=0.078 for 6100 reflections. The title complex has pentagonal bipyramid configuration in which the zirconium atom is coordinated by one CH_3C_5H_4 group and three bidentate dibenzyldithiocarbamate ligands.展开更多
Cp;ZrCl(S;CNBz;) is a five-coordinate bent zirconocene in which the dibenzyldithiocarbamate is a bidentate ligand (Zr-Cl 2.549(1)A; Zr-C 2.489-2.533; Zr-S 2.667(1), 2.734(1); Zr-Cl-S1 137.6(1);; Zr-Cl-S2 73....Cp;ZrCl(S;CNBz;) is a five-coordinate bent zirconocene in which the dibenzyldithiocarbamate is a bidentate ligand (Zr-Cl 2.549(1)A; Zr-C 2.489-2.533; Zr-S 2.667(1), 2.734(1); Zr-Cl-S1 137.6(1);; Zr-Cl-S2 73.3(1);).展开更多
The compound phenol,2-[4(S)-4,5-dihydro-4-phenyl-2-ozazolinyl(1,C15H13NO2) was synthesized with a simple,one step method free of water and air.It was obtained in a moderate yield from the reaction of 2-hydroxybenz...The compound phenol,2-[4(S)-4,5-dihydro-4-phenyl-2-ozazolinyl(1,C15H13NO2) was synthesized with a simple,one step method free of water and air.It was obtained in a moderate yield from the reaction of 2-hydroxybenzonitrile with optically active amino alcohol in chloroben-zene under dry,anaerobic conditions.It belongs to the orthorhombic system,space group P212121 with a = 5.786(5),b = 10.730(5),c = 19.722(5),C15H13NO2,Mr = 239.26,V = 1224.4(12)3,Z = 4 and Dc = 1.298 mg/m3.The final R = 0.0324 for 1627 observed reflections with Ⅰ 〉 2σ(Ⅰ) and Rw = 0.0826 for all data.The structure of compound 1 was determined by X-ray diffraction,NMR and HRMS.展开更多
The present study uses textual function of metafunction in Halliday’s Systemic Functional Grammar as the theoretical framework,focusing on Thematic structures of political discourses.This thesis moves on to analyze t...The present study uses textual function of metafunction in Halliday’s Systemic Functional Grammar as the theoretical framework,focusing on Thematic structures of political discourses.This thesis moves on to analyze the State of the Union Address and its Chinese version from the perspective of a contrastive study,aiming to find out English-Chinese translation approaches.The study findings give rise to two implications for E-C translation in Obama’s Address For one thing,a thematic structure,without any change of word orders,can be directly translated into a SV pattern in a topic-comment structure.For another,it has to be restructured into non-SV patterns.It helps to apply the strategy in the target text of Obama’s State of the Union Address.展开更多
For current physical examination and medical institutions, the majority of Medical projects need a long time to get the result, this wastes user too much time. In order to solve this problem, this paper presents a pro...For current physical examination and medical institutions, the majority of Medical projects need a long time to get the result, this wastes user too much time. In order to solve this problem, this paper presents a program to achieve viewing the results of examination anytime or anywhere with the help of cell phone applications software. The program proposed to solve the problem that user have to wait for the medical test results for a long time and cause the time waste, compared to the programs which using e-mail, SMS and mailing report card to inform the user the results, this one is to be more efficient, while also better meet user and medical institutions’ requirements. In addition, in order to test the practicality and feasibility of the program, with IOS devices as the material basis, this paper constructs a Web client system, based on the GPRS technology, we can realize the data communications between the Web server and a client which is the workbench IOS devices. Through testing, we can proof this Web client system has certain practical and development value, with the physical examination institutions become popular gradually, I believe that this design ideas of the system will be used extensively in the medical system, and also will bring a person more convenient.展开更多
文摘E-learning platforms support education systems worldwide, transferring theoretical knowledge as well as soft skills. In the present study high-school pupils’, and adult students’ opinions were evaluated through a modern structured MOODLE interactive course, designed for the needs of the laboratory course “Automotive Systems”. The study concerns Greek secondary vocational education pupils aged 18 and vocational training adult students aged 20 to 50 years. The multistage, equal size simple random cluster sample was used as a sampling method. Pupils and adult students of each cluster completed structured 10-question questionnaires both before and after attending the course. A total of 120 questionnaires were collected. In general, our findings disclosed that the majority of pupils and adult students had significantly improved their knowledge and skills from using MOODLE. They reported strengthening conventional teaching, using the new MOODLE technology. The satisfaction indices improved quite, with the differences in their mean values being statistically significant.
文摘Based on the multiplicity results of Benci and Fortunato [4], we consider some elliptic systems with strongly indefinite quadratic part, and establish the existence of infinitely many nontrivial solutions in a suitable family of products of fractional Sobolev spaces.
文摘The basic concepts about the active structures and some attributes of the modes were presented in paper “Liner Active Structures and Modes]( I) ". The characteristics of the active discrete systems and active beams were discussed, especially, the stability of the active structures and the orthogonality of the eigenvectors. The notes about modes were portrayed by a model of a seven-storeyed building with sensors and actuators. The concept of the adjoint active structure was extended from the discrete systems to the beams that were the representations of the continuous structures. Two types of beams with different placements of the measuring and actuating systems were discussed in detail. One is the beam with the discrete sensors and actuators, and the other is the beam with distributed sensor and actuator function. The orthogonality conditions were derived with the modal shapes of the active beam and its adjoint active beam. An example shows that the variation of eigenvalues with feedback amplitude for the homo-configuration and non-homo-configuration active structures.
基金Funded by the National Basic Research Program of China (973 Program) (No. 2009CB623201)the National Natural Science Foundation of China (No.51072150)
文摘The samples of the C-S-H series were synthesized by hydrothermal reaction of fumed silica, CaO and deionized water at initial C/S ratios between 1.0-1.7. Phase composition and structural and morphology characteristics of C-S-H samples were analyzed by XRD, IR and SEM. The experimental results showed that the d-spacing of (002), (110) and (020) decreased, the d-spacing of (200) increased, and the d-spacing of (310) varied randomly, the polymerization of silica tetrahedra of C-S-H decreased, and morphology of C-S-H samples varied from sheet shapes to long reticular fibers as C/S ratio increased.
文摘According to specifications for Welding Procedure Qualification of ASME IX Section and Chinese code, JB 4708 2000, a software package for managing welding documents has been rebuilt. Consequently, the new software package can be used in a Limited Area Network (LAN) with 4 different levels of authorities for different users. Therefore, the welding documents, including DWPS (Design for Welding Procedure Specifications), PQRs (Procedure Qualification Records) and WPS (Welding Procedure Specifications) can be shared within a company. At the same time, the system provides users various functions such as browsing, copying, editing, searching and printing records, and helps users to make decision of whether a new PQR test is necessary or not according to the codes above as well. Furthermore, super users can also browse the history of record modification and retrieve the records when needed.
基金Funded by National Natural Science Foundation of China(Nos51072150,51272193)Program for New Century Excellent Talents inUniversity(No.NCET-10-0660)the Fundamental Research Fundsfor the Central Universities(Nos.2012-Ia-010,2013-Ia-015)
文摘The effects of polyaerylamide (PAM) and polyvinyl alcohol (PVA) on morphology and structure of calcium silica~ hydrate with C/S 1.0-1.7 prepared via precipitation in solution were investigated by XRD, FT-IR and TEM techniques. The results show that incorporation of the polymers decreased the order degree, increased the interlayer spacing and disturbed the layered stacking of C-S-H. Interlayer spacing expansion depended on C/S ratios and type of polymer. Interlayer spacing expansion had a minimum at C/S 1.0 and a maximum at C/S 1.3 and 1.5. Interlayer spacing expansion of PAM was bigger than that of PVA with the same C/S. C-S-H added with PVA mainly exhibited foil-like and fibrillar morphology. The fibrils were of variable length from a few tens of nanometers to a few hundreds of nanometers. Fibrils or foils seemed to be longer in the presence of PVA.
基金This project was supported by the China Postdoctoral Science Foundation,Henan Postdoctoral Science Foundation,NCWU 2017 Annual Teaching Teacher Training Object ProjectKey Research Projects of Higher Education in Henan Province(18B150010)+1 种基金the Key Scientific Research Project of Henan Higher Education(No.17A520011)the Science and Technology Research Project of Henan Province(182102110029)
文摘Impurity formation energy, electronic structure, and photocatalytic properties of C-, N-, or S-doped BiOCl are investigated by density-functional theory plus U calculations(DFT + U). Results show that the doping effect of S is better than that of C or N on the tunable photocatalytic activities of BiOCl. At low concentration, S-doped BiOCl systems are the most stable under Bi-rich growth conditions because of their lower impurity-formation energy. Compared with the electronic structures of S-doped BiOCl, C-or N-doped BiOCl have relatively deeper impurity energy levels appearing in their band gap(except Bi_(36)O_(35)NCl_(36)), which may act as photogenerated carrier-recombination centers and reduce photocatalytic activity. At high concentration, S is substituted on the O lattice site system, whereas some S 3p states mix with the valence band; this mixture leads to an obvious band-gap decrease and continuum-state formation above the valence-band edge of BiOCl. Such activity is advantageous to photochemical catalysis response. Compared with pure Bi OCl and a low-concentration S-doped system, a high-concentration S-doped system shows an obvious redshift on the absorption edge and has better photocatalytic O_2 evolution performance.
文摘(PPh_3)_2Ni(i-mnt),(i-mnt=S_2C=C(CN)_2),Mr=613.43,monoclinic,Pn,a=9.167(3),b=10.872(3), c=18.209(7) ,β=101.46(3)°,V=1779(1) ,Z=2,Dc=1.15 g/cm^3,λ(Moka)=0.71069 ,μ=7.67 cm^(-1), F(000)=648,T=296K,final R=0.060,Rw=0.073 for 1909 observed reflections with Ⅰ≥3σ(Ⅰ).The complex adopts a square planar geometry as its coordination unit,the mean Ni-S and Ni-P distances are 2.216 and 2.221 ,respectivety.
文摘In the paper, dicalcium silicate (C2S) was modified to obtain higher performance, and the solutionizing pattern of BaSO4 in cement clinker was analyzed theoretically. According to experimental results, solutionizing of BaSO4in cement clinker improved crystal plane distance of C2S as well as the relations of coordination. The performance tests show that the strength of C2S modified by BaSO4 changes and the reactivity of C2S increases significantly.
文摘BACKGROUND Systemic lupus erythematosus(SLE)is an autoimmune disease characterized by systemic involvement and multiple autoantibodies in the serum.Patients with protein C(PC)and protein S(PS)deficiency are prone to thrombosis.In contrast,patients with primary hyperfibrino-lysis tend to bleed.CASE SUMMARY A 52-year-old female patient with bilateral pleural effusion was diagnosed with"tuberculous pleurisy"and treated with anti-tuberculosis drugs and prednisone.The coagulation-related laboratory results showed decreased fibrinogen,PC activity,PS activity,and antithrombinШactivity.The immune-related laboratory results showed positive antinuclear antibody,anti-Smith antibody,anticardiolipin antibody(ACL),anti-β2-glycoprotein I antibody(aβ2GPI)and direct Coomb’s test and decreased complement 3 and complement 4.Thoracoscopy was performed and bloody pleural fluid was drained.Pathology of the pleural biopsy showed lymphocytes,plasma cells,and a few eosinophils in adipose and fibrous connective tissue.Results of whole exome sequencing of blood showed no genetic mutations suggesting the presence of hereditary hematological diseases.The patient was finally diagnosed with SLE and primary hyperfibrinolysis,and was treated with prednisolone,hydroxychloroquine,and compound cyclophosphamide.CONCLUSION PC and PS deficiency in SLE might be related to ACL and aβ2GPI.SLE and primary hyperfibrinolysis can coexist in one patient,with both a risk of thrombosis and a risk of bleeding.
文摘This paper aimed at studying the effect of different types of soil tillage systems on the change of total carbon (C) and nitrogen (N) in the soil structural units of different size after dry structural analysis of soil. The research was carried out in a 6-field rotation system (grain maize-wheat-sunflower-wheat-bean-wheat) at the end of the 2nd rotation. Six out of 24 soil tillage systems were selected; they were applied independently and in combination in the crop rotation. After that, they were compared to the system with constant deep plowing. So a total of seven soil tillage systems were investigated. The selected systems for main soil tillage were the following: plowing (control variant), disking, cutting, nil tillage (direct sowing), plowing-disking, plowing-nil tillage, disking-nil tillage. Three depths of 0-10, 10-20 and 20-30 cm were studied, as well as soil structural units were of the following sizes: 〉 10 mm, 10-5, 5-3, 3-1, 1-0.25 mm and 〈 0.25 mm. As a result of systematic implementation of different soil tillage systems, higher N and C concentrations were established by the layers according to constant plowing. Constant disking and its alternation with nil tillage increased the total N concentration with 15.6% and 11.1%, respectively, in comparison with the constant plowing. The same was valid for C concentration in soil, but the highest increase was established in the variants with constant cutting and nil tillage. The exceeding was with 14.0% and 13.2%, in comparison to constant plowing. The redistribution of N and C depending on the structural soil units was most expressed in the 0-10 cm and 10-20 cm layers. The highest amounts of C and N were found in the soil units with size less than 5 mm, mainly in the 〈 0.25 mm fraction. At depth of 20-30 cm, the role of the size of soil structural units for C and N redistribution decreased strongly. The values of C/N ratio were moderate only under the use of constant disking. This index was low under all other soil tillage systems. The correlation of total N with C in soil was high, positive and significant depending on the size of structural soil units and the tillage systems, as average for the investigated factors in this experiment. The minimal tillage and the tillage without turning of soil, used independently and in combination, had the highest contribution to preserving the organic matter in the haplic Chernozems of Dobrudzha region.
文摘(CH_3C_5H_4)Zr(S_2CNBz_2)_3, Mr=987.55, space group P1, a=13.002(4), b=13.659(3), c=29.685(8); α=100.72(2)~o,β=97.23(2)~o, γ=105.36(2)~o; V=4909(2)~3, Z=4, Dc=1.34gcm^(-3), Mo-K(λ=0.71073A) radiation, μ=5.0cm^(-1), R=0.069, Rw=0.078 for 6100 reflections. The title complex has pentagonal bipyramid configuration in which the zirconium atom is coordinated by one CH_3C_5H_4 group and three bidentate dibenzyldithiocarbamate ligands.
文摘Cp;ZrCl(S;CNBz;) is a five-coordinate bent zirconocene in which the dibenzyldithiocarbamate is a bidentate ligand (Zr-Cl 2.549(1)A; Zr-C 2.489-2.533; Zr-S 2.667(1), 2.734(1); Zr-Cl-S1 137.6(1);; Zr-Cl-S2 73.3(1);).
文摘The compound phenol,2-[4(S)-4,5-dihydro-4-phenyl-2-ozazolinyl(1,C15H13NO2) was synthesized with a simple,one step method free of water and air.It was obtained in a moderate yield from the reaction of 2-hydroxybenzonitrile with optically active amino alcohol in chloroben-zene under dry,anaerobic conditions.It belongs to the orthorhombic system,space group P212121 with a = 5.786(5),b = 10.730(5),c = 19.722(5),C15H13NO2,Mr = 239.26,V = 1224.4(12)3,Z = 4 and Dc = 1.298 mg/m3.The final R = 0.0324 for 1627 observed reflections with Ⅰ 〉 2σ(Ⅰ) and Rw = 0.0826 for all data.The structure of compound 1 was determined by X-ray diffraction,NMR and HRMS.
文摘The present study uses textual function of metafunction in Halliday’s Systemic Functional Grammar as the theoretical framework,focusing on Thematic structures of political discourses.This thesis moves on to analyze the State of the Union Address and its Chinese version from the perspective of a contrastive study,aiming to find out English-Chinese translation approaches.The study findings give rise to two implications for E-C translation in Obama’s Address For one thing,a thematic structure,without any change of word orders,can be directly translated into a SV pattern in a topic-comment structure.For another,it has to be restructured into non-SV patterns.It helps to apply the strategy in the target text of Obama’s State of the Union Address.
文摘For current physical examination and medical institutions, the majority of Medical projects need a long time to get the result, this wastes user too much time. In order to solve this problem, this paper presents a program to achieve viewing the results of examination anytime or anywhere with the help of cell phone applications software. The program proposed to solve the problem that user have to wait for the medical test results for a long time and cause the time waste, compared to the programs which using e-mail, SMS and mailing report card to inform the user the results, this one is to be more efficient, while also better meet user and medical institutions’ requirements. In addition, in order to test the practicality and feasibility of the program, with IOS devices as the material basis, this paper constructs a Web client system, based on the GPRS technology, we can realize the data communications between the Web server and a client which is the workbench IOS devices. Through testing, we can proof this Web client system has certain practical and development value, with the physical examination institutions become popular gradually, I believe that this design ideas of the system will be used extensively in the medical system, and also will bring a person more convenient.