In this work, we successfully synthesized bicrystalline anatase/TiO2（B） nanofibre and used it as active substrate for surface-enhanced Raman scattering （SERS） applications. The bicrystalline structured TiO2 substr...In this work, we successfully synthesized bicrystalline anatase/TiO2（B） nanofibre and used it as active substrate for surface-enhanced Raman scattering （SERS） applications. The bicrystalline structured TiO2 substrates provide additional charge transfer across the anatase-TiO2（B） interface and thus enhanced activity compared to the pure single crystalline phase. With an effort to further increase the sensitivity of SERS, nitrogen element was doped into bicrystalline anatase/TiO2（B） nanofibres （N-TiO2） and higher SERS enhancement was achieved. The nitrogen content was controlled by tuning the calcination temperature of titanate precursor at 500, 600 and 700℃, respectively. The sample calcined at 600℃ （NT600） acquires the highest percentage of nitrogen element due to its open pore structure that facilitates the diffusion of nitrogen during calcination. Raman intensity depends on the amount of nitrogen doping, thus NT600 exhibited the best SERS activity. The doped nitrogen in TiO2 facilitates the charge transfer between TiO2 and probing molecules and thus suppresses the electron-hole recombination. This work provides a new perspective on the design of efficient TiO2 SERS active substrate and is expected to be valuable for adsorbate detection on semiconductor surface.展开更多
The unicellular cyanobacterium Synechocystis sp. PCC 6803, a model organism known for its unique combination of highly desirable molecular genetic, physiological and morphological characteristics, was employed in the ...The unicellular cyanobacterium Synechocystis sp. PCC 6803, a model organism known for its unique combination of highly desirable molecular genetic, physiological and morphological characteristics, was employed in the present study. The species was cultured in BG11 liquid medium contained various initial concentrations of Pb^2＋ and Cd〉 （0, 0.5, 1, 2, 4, 6 and 8 mg/L）. The experiment was conducted for six days and the metal induced alterations in the ultrastructure, growth and pigment contents were assessed. Alterations in the ultrastructure of the Synechocystis sp. PCC 6803 cells became evident with the increased （〉4 mg/L Pb^2＋） metal concentration. The photosynthetic apparatus （thylakoid membranes） were found to be the worst affected. Deteriorated or completely destroyed thylakoid membranes have made large empty spaces in the cell interior. In addition, at the highest concentration （8 mg/L pb^2＋）, the polyphosphate granules became more prominent both in size and number. Despite the initial slight stimulations （0.2, 3.8 and 6.5% respectively at 0.5, 1 and 2 mg/L pb^2＋）, both metals inhibited the growth in a dose-dependent manner as incubation progressed. Pigment contents （chlorophyll a, 13 carotene and phycocyanin） were also decreased with increasing metal concentration. Cells exposed to 6 mg/L Pb^2＋, resulted in 36.56, 37.39 and 29.34% reductions of chlorophyll a, 13 carotene and phycocyanin respectively over the control. Corresponding reductions for the same CdZ＋concentrations were 57.83, 48.94 and 56.90%. Lethal concentration （96 h LC50） values （3.47 mg/L Cd^2＋ and 12.11 mg/L Pb^2＋） indicated that Synechocystis sp. PCC 6803 is more vulnerable to Cd^2＋ than Pb^2＋.展开更多
In general, to reconstruct the accurate shape of buildings, we need at least one stereomodel （two photographs） for each building. In most cases, however, only a single non-metric photograph is available, which is us...In general, to reconstruct the accurate shape of buildings, we need at least one stereomodel （two photographs） for each building. In most cases, however, only a single non-metric photograph is available, which is usually obtained either by an amateur, such as a tourist, or from a newspaper or a post card. To evaluate the validity of 3D reconstruction from a single non-metric image, this study analyzes the effects of object depth on the accuracy of dimensional shape in X and Y directions using a single non-metric image by means of simulation technique, as this was considered to be, in most cases, a main source of data acquisition in recording and documenting buildings.展开更多
In recent years, Edwardsiella tarda has become one of the most deadly pathogens of Japanese fl ounder( Paralichthys olivaceus), causing serious annual losses in commercial production. In contrast to the rapid advances...In recent years, Edwardsiella tarda has become one of the most deadly pathogens of Japanese fl ounder( Paralichthys olivaceus), causing serious annual losses in commercial production. In contrast to the rapid advances in the aquaculture of P. o livaceus, the study of E. tarda resistance-related markers has lagged behind, hindering the development of a disease-resistant strain. Thus, a marker-trait association analysis was initiated, combining bulked segregant analysis(BSA) and quantitative trait loci(QTL) mapping. Based on 180 microsatellite loci across all chromosomes, 106 individuals from the F1333(♀: F0768 ×♂: F0915)(Nomenclature rule: F+year+family number) were used to detect simple sequence repeats(SSRs) and QTLs associated with E. tarda resistance. After a genomic scan, three markers(Scaffold 404-21589, Scaffold 404-21594 and Scaffold 270-13812) from the same linkage group(LG)-1 exhibited a signifi cant difference between DNA, pooled/bulked from the resistant and susceptible groups( P <0.001). Therefore, 106 individuals were genotyped using all the SSR markers in LG1 by single marker analysis. Two different analytical models were then employed to detect SSR markers with different levels of signifi cance in LG1, where 17 and 18 SSR markers were identifi ed, respectively. Each model found three resistance-related QTLs by composite interval mapping(CIM). These six QTLs, designated q E1–6, explained 16.0%–89.5% of the phenotypic variance. Two of the QTLs, q E-2 and q E-4, were located at the 66.7 c M region, which was considered a major candidate region for E. tarda resistance. This study will provide valuable data for further investigations of E. tarda resistance genes and facilitate the selective breeding of disease-resistant Japanese fl ounder in the future.展开更多
Based on a variety of case histories of site investigations, including extensive bore hole data, laboratory testing and geophysical prospecting at more than 550 construction sites, an empirical formulation is proposed...Based on a variety of case histories of site investigations, including extensive bore hole data, laboratory testing and geophysical prospecting at more than 550 construction sites, an empirical formulation is proposed for the rapid determination of allowable bearing pressure of shallow foundations in soils and rocks. The proposed expression corroborates consistently with the results of the classical theory and is proven to be rapid, and reliable. Plate load tests have been also carried out at three different sites, in order to further confirm the validity of the proposed method. It consists of only two soil parameters, namely, the in situ measured shear wave velocity and the unit weight. The unit weight may be also determined with sufficient accuracy, by means of other empirical expressions proposed, using P or S -- wave velocities. It is indicated that once the shear and P-wave velocities are measured in situ by an appropriate geophysical survey, the allowable bearing pressure as well as the coefficient of subgrade reaction and many other elasticity parameters may be determined rapidly and reliably.展开更多
We present a new quantum protocol for solving detectable Byzantine agreement problem between threeparties by employing one quantum key distribution protocol.The protocol is suggested by a special four-qubit entangleds...We present a new quantum protocol for solving detectable Byzantine agreement problem between threeparties by employing one quantum key distribution protocol.The protocol is suggested by a special four-qubit entangledstate instead of singlet states,which shows that singlet states are not necessary to achieve detectable Byzantine agreement.展开更多
The experiment was carried out in a private orchard situated at Atrush town, Duhok Govemorate Kurdistan Region-Iraq during 2011 season to study the effect of foliar application of three concentrations of potassium （0...The experiment was carried out in a private orchard situated at Atrush town, Duhok Govemorate Kurdistan Region-Iraq during 2011 season to study the effect of foliar application of three concentrations of potassium （0.0%, 0.5% and 1%） and three concentrations of copper （0.0%, 0.02% and 0.04%） on an eight years old peach cultivar, planted in clay soil, spaced at 4.0 m x 4.0 m. The foliar application was done twice, on April 24, 2011 and May 25, 2011. The results showed that spraying of potassium at both concentration （0.5% and 1%） or copper at high concentration （0.04%） had a positive effect on leaf area, leaf fresh weight, leaf dry weight, total chlorophyll, fruit weight, fruit number and yield per tree as well as fruit diameter, pith thick, pulp weight, seed weight and total soluble solid. The interaction between potassium and copper significantly enhanced all detected traits, since trees receiving 1% and sprayed with 0.04% of copper was characterized by the highest values of all growth and yield characteristics compared to the lowest values at untreated trees （control）.展开更多
Micro/nanostructures have broad applications in diverse application fields, such as surface enhanced Raman spectroscopy (SERS), photocatalysis, field emission, photonic crystals, microfluidic devices, electrochemical ...Micro/nanostructures have broad applications in diverse application fields, such as surface enhanced Raman spectroscopy (SERS), photocatalysis, field emission, photonic crystals, microfluidic devices, electrochemical devices, etc. Using polystyrene (PS) spheres formed monolayer colloidal crystal templates as masks, scaffolds, or molds with different materials growth techniques, many different periodic nanostructured arrays can be obtained with the building units varied from nanoparticles, nanopores, nanorings, nanorods, to nanoshells. Significant progresses have been made on the synthesis of micro/nanostructures with efficient SERS response. In this review, we mainly focus on the various PS template-based fabrication techniques in realizing micro/nanostructured arrays and the SERS applications.展开更多
Lightweight geomaterial（LWGM）possesses such merit characteristics as low unit weight,environmental protection（recycling these materials instead of stockpiling them）,buffering mechanical property and thermal insula...Lightweight geomaterial（LWGM）possesses such merit characteristics as low unit weight,environmental protection（recycling these materials instead of stockpiling them）,buffering mechanical property and thermal insulation[1].LWGM,an attractive substitute for earth fills,展开更多
Dual-modal surface enhanced Raman spectrum(SERS)-fluorescence polymer/metal hybrid complexes have been prepared for tracing drug release process in tumor cells. Firstly, the hyperbranched poly((S-(4-vinyl) benzyl S′-...Dual-modal surface enhanced Raman spectrum(SERS)-fluorescence polymer/metal hybrid complexes have been prepared for tracing drug release process in tumor cells. Firstly, the hyperbranched poly((S-(4-vinyl) benzyl S′-propyltrithiocarbonate)-co-(poly(ethylene glycol) methacrylate))(HPVBEG) was synthesized via the combination of reversible addition-fragmentation chain-transfer(RAFT) polymerization and self-condensing vinyl polymerization(SCVP). Subsequently, the anticancer drug doxorubicin(DOX) was linked to HPVBEG via pH sensitive Schiff base bonds to form HPVBEG-g-DOX conjugates.Through aminolysis reaction, HPVBEG-g-DOX was coordinated with gold nanoparticles(GNP), resulting in the formation of HPVBEG-g-DOX/GNP complexes. In neutral condition, the HPVBEG-g-DOX/GNP complexes were stable, and DOX was bound to the surface of GNPs. Therefore, the SERS of DOX could be observed, while the fluorescence of DOX was quenched by GNPs. Under an acidic environment, DOX was released from the surface of GNPs with breakage of Schiff base bonds.Thus, the SERS signal of DOX was gradually reduced. Correspondingly, the fluorescence signal of DOX was enhanced.Through dual-modal SERS-fluorescence technique, the DOX delivery and release process was traced in tumor cells. Moreover,the viability of MCF-7 cells incubated with HPVBEG-g-DOX/GNP complexes was investigated by Cell Counting Kit-8(CCK-8) assay. The experimental results showed that HPVBEG-g-DOX/GNP complexes had similar proliferation inhibition effect compared with free DOX. Definitely, the dual-modal SERS-fluorescence complexes for tracing drug delivery and release will have promising prospects on tumor diagnosis and therapy.展开更多
We perform an in-plane optical spectroscopy measurement on high quality FeSe single crystals grown by a vapor transport technique. Below the structural transition at Ts - 90 K, the reflectivity spectrum clearly shows ...We perform an in-plane optical spectroscopy measurement on high quality FeSe single crystals grown by a vapor transport technique. Below the structural transition at Ts - 90 K, the reflectivity spectrum clearly shows a gradual suppression around 400 cm-1 and the conductivity spectrum shows a peak at higher frequency. The energy scale of this gap-like feature is comparable to the width of the band splitting observed by ARPES. The low-frequency conductivity consists of two Drude components and the overall plasma frequency is smaller than that of the FeAs based compounds, suggesting a lower cartier density or stronger correlation effect. The plasma frequency becomes even smaller below Ts which agrees with the very small Fermi energy estimated by other experiments. Similar to iron pnictides, a clear temperature-induced spectral weight transfer is observed for FeSe, being indicative of strong correlation effect.展开更多
基金Supported by Chinese MOST 973 project(2013CB733501)the National Natural Science Foundation of China1(21136004,21476106,21606131)+1 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the Fundamental Research Funds for the Central Universities(30916011351)at Nanjing University of Science&Technology
文摘In this work, we successfully synthesized bicrystalline anatase/TiO2（B） nanofibre and used it as active substrate for surface-enhanced Raman scattering （SERS） applications. The bicrystalline structured TiO2 substrates provide additional charge transfer across the anatase-TiO2（B） interface and thus enhanced activity compared to the pure single crystalline phase. With an effort to further increase the sensitivity of SERS, nitrogen element was doped into bicrystalline anatase/TiO2（B） nanofibres （N-TiO2） and higher SERS enhancement was achieved. The nitrogen content was controlled by tuning the calcination temperature of titanate precursor at 500, 600 and 700℃, respectively. The sample calcined at 600℃ （NT600） acquires the highest percentage of nitrogen element due to its open pore structure that facilitates the diffusion of nitrogen during calcination. Raman intensity depends on the amount of nitrogen doping, thus NT600 exhibited the best SERS activity. The doped nitrogen in TiO2 facilitates the charge transfer between TiO2 and probing molecules and thus suppresses the electron-hole recombination. This work provides a new perspective on the design of efficient TiO2 SERS active substrate and is expected to be valuable for adsorbate detection on semiconductor surface.
文摘The unicellular cyanobacterium Synechocystis sp. PCC 6803, a model organism known for its unique combination of highly desirable molecular genetic, physiological and morphological characteristics, was employed in the present study. The species was cultured in BG11 liquid medium contained various initial concentrations of Pb^2＋ and Cd〉 （0, 0.5, 1, 2, 4, 6 and 8 mg/L）. The experiment was conducted for six days and the metal induced alterations in the ultrastructure, growth and pigment contents were assessed. Alterations in the ultrastructure of the Synechocystis sp. PCC 6803 cells became evident with the increased （〉4 mg/L Pb^2＋） metal concentration. The photosynthetic apparatus （thylakoid membranes） were found to be the worst affected. Deteriorated or completely destroyed thylakoid membranes have made large empty spaces in the cell interior. In addition, at the highest concentration （8 mg/L pb^2＋）, the polyphosphate granules became more prominent both in size and number. Despite the initial slight stimulations （0.2, 3.8 and 6.5% respectively at 0.5, 1 and 2 mg/L pb^2＋）, both metals inhibited the growth in a dose-dependent manner as incubation progressed. Pigment contents （chlorophyll a, 13 carotene and phycocyanin） were also decreased with increasing metal concentration. Cells exposed to 6 mg/L Pb^2＋, resulted in 36.56, 37.39 and 29.34% reductions of chlorophyll a, 13 carotene and phycocyanin respectively over the control. Corresponding reductions for the same CdZ＋concentrations were 57.83, 48.94 and 56.90%. Lethal concentration （96 h LC50） values （3.47 mg/L Cd^2＋ and 12.11 mg/L Pb^2＋） indicated that Synechocystis sp. PCC 6803 is more vulnerable to Cd^2＋ than Pb^2＋.
文摘In general, to reconstruct the accurate shape of buildings, we need at least one stereomodel （two photographs） for each building. In most cases, however, only a single non-metric photograph is available, which is usually obtained either by an amateur, such as a tourist, or from a newspaper or a post card. To evaluate the validity of 3D reconstruction from a single non-metric image, this study analyzes the effects of object depth on the accuracy of dimensional shape in X and Y directions using a single non-metric image by means of simulation technique, as this was considered to be, in most cases, a main source of data acquisition in recording and documenting buildings.
基金Supported by the National Natural Science Foundation of China(No.31461163005)the Taishan Scholar Project of Shandong Province
文摘In recent years, Edwardsiella tarda has become one of the most deadly pathogens of Japanese fl ounder( Paralichthys olivaceus), causing serious annual losses in commercial production. In contrast to the rapid advances in the aquaculture of P. o livaceus, the study of E. tarda resistance-related markers has lagged behind, hindering the development of a disease-resistant strain. Thus, a marker-trait association analysis was initiated, combining bulked segregant analysis(BSA) and quantitative trait loci(QTL) mapping. Based on 180 microsatellite loci across all chromosomes, 106 individuals from the F1333(♀: F0768 ×♂: F0915)(Nomenclature rule: F+year+family number) were used to detect simple sequence repeats(SSRs) and QTLs associated with E. tarda resistance. After a genomic scan, three markers(Scaffold 404-21589, Scaffold 404-21594 and Scaffold 270-13812) from the same linkage group(LG)-1 exhibited a signifi cant difference between DNA, pooled/bulked from the resistant and susceptible groups( P <0.001). Therefore, 106 individuals were genotyped using all the SSR markers in LG1 by single marker analysis. Two different analytical models were then employed to detect SSR markers with different levels of signifi cance in LG1, where 17 and 18 SSR markers were identifi ed, respectively. Each model found three resistance-related QTLs by composite interval mapping(CIM). These six QTLs, designated q E1–6, explained 16.0%–89.5% of the phenotypic variance. Two of the QTLs, q E-2 and q E-4, were located at the 66.7 c M region, which was considered a major candidate region for E. tarda resistance. This study will provide valuable data for further investigations of E. tarda resistance genes and facilitate the selective breeding of disease-resistant Japanese fl ounder in the future.
文摘Based on a variety of case histories of site investigations, including extensive bore hole data, laboratory testing and geophysical prospecting at more than 550 construction sites, an empirical formulation is proposed for the rapid determination of allowable bearing pressure of shallow foundations in soils and rocks. The proposed expression corroborates consistently with the results of the classical theory and is proven to be rapid, and reliable. Plate load tests have been also carried out at three different sites, in order to further confirm the validity of the proposed method. It consists of only two soil parameters, namely, the in situ measured shear wave velocity and the unit weight. The unit weight may be also determined with sufficient accuracy, by means of other empirical expressions proposed, using P or S -- wave velocities. It is indicated that once the shear and P-wave velocities are measured in situ by an appropriate geophysical survey, the allowable bearing pressure as well as the coefficient of subgrade reaction and many other elasticity parameters may be determined rapidly and reliably.
基金Supported by National Natural Science Foundation of China under Grant Nos.60873191,60903152,and 60821001SRFDP under Grant No.200800131016+5 种基金Beijing Nova Program under Grant No.2008B51Key Project of Chinese Ministry of Education under Grant No.109014Beijing Natural Science Foundation under Grant No.4072020China Postdoctoral Science Foundation under Grant No.20090450018National Laboratory for Modern Communications Science Foundation of China under Grant No.9140C1101010601ISN Open Foundation
文摘We present a new quantum protocol for solving detectable Byzantine agreement problem between threeparties by employing one quantum key distribution protocol.The protocol is suggested by a special four-qubit entangledstate instead of singlet states,which shows that singlet states are not necessary to achieve detectable Byzantine agreement.
文摘The experiment was carried out in a private orchard situated at Atrush town, Duhok Govemorate Kurdistan Region-Iraq during 2011 season to study the effect of foliar application of three concentrations of potassium （0.0%, 0.5% and 1%） and three concentrations of copper （0.0%, 0.02% and 0.04%） on an eight years old peach cultivar, planted in clay soil, spaced at 4.0 m x 4.0 m. The foliar application was done twice, on April 24, 2011 and May 25, 2011. The results showed that spraying of potassium at both concentration （0.5% and 1%） or copper at high concentration （0.04%） had a positive effect on leaf area, leaf fresh weight, leaf dry weight, total chlorophyll, fruit weight, fruit number and yield per tree as well as fruit diameter, pith thick, pulp weight, seed weight and total soluble solid. The interaction between potassium and copper significantly enhanced all detected traits, since trees receiving 1% and sprayed with 0.04% of copper was characterized by the highest values of all growth and yield characteristics compared to the lowest values at untreated trees （control）.
基金supported by the National Natural Science Foundation of China(Grant Nos.51371131,11375134,51571153)Jiangsu Provincial Natural Science Foundation(Grant No.BK20141217)the Fundamental Research Funds for the Central Universities(Grant No.2042015kf1012)
文摘Micro/nanostructures have broad applications in diverse application fields, such as surface enhanced Raman spectroscopy (SERS), photocatalysis, field emission, photonic crystals, microfluidic devices, electrochemical devices, etc. Using polystyrene (PS) spheres formed monolayer colloidal crystal templates as masks, scaffolds, or molds with different materials growth techniques, many different periodic nanostructured arrays can be obtained with the building units varied from nanoparticles, nanopores, nanorings, nanorods, to nanoshells. Significant progresses have been made on the synthesis of micro/nanostructures with efficient SERS response. In this review, we mainly focus on the various PS template-based fabrication techniques in realizing micro/nanostructured arrays and the SERS applications.
文摘Lightweight geomaterial（LWGM）possesses such merit characteristics as low unit weight,environmental protection（recycling these materials instead of stockpiling them）,buffering mechanical property and thermal insulation[1].LWGM,an attractive substitute for earth fills,
基金supported by the National Basic Research Program of China(2015CB931801)the National Natural Science Foundation of China(51473093)
文摘Dual-modal surface enhanced Raman spectrum(SERS)-fluorescence polymer/metal hybrid complexes have been prepared for tracing drug release process in tumor cells. Firstly, the hyperbranched poly((S-(4-vinyl) benzyl S′-propyltrithiocarbonate)-co-(poly(ethylene glycol) methacrylate))(HPVBEG) was synthesized via the combination of reversible addition-fragmentation chain-transfer(RAFT) polymerization and self-condensing vinyl polymerization(SCVP). Subsequently, the anticancer drug doxorubicin(DOX) was linked to HPVBEG via pH sensitive Schiff base bonds to form HPVBEG-g-DOX conjugates.Through aminolysis reaction, HPVBEG-g-DOX was coordinated with gold nanoparticles(GNP), resulting in the formation of HPVBEG-g-DOX/GNP complexes. In neutral condition, the HPVBEG-g-DOX/GNP complexes were stable, and DOX was bound to the surface of GNPs. Therefore, the SERS of DOX could be observed, while the fluorescence of DOX was quenched by GNPs. Under an acidic environment, DOX was released from the surface of GNPs with breakage of Schiff base bonds.Thus, the SERS signal of DOX was gradually reduced. Correspondingly, the fluorescence signal of DOX was enhanced.Through dual-modal SERS-fluorescence technique, the DOX delivery and release process was traced in tumor cells. Moreover,the viability of MCF-7 cells incubated with HPVBEG-g-DOX/GNP complexes was investigated by Cell Counting Kit-8(CCK-8) assay. The experimental results showed that HPVBEG-g-DOX/GNP complexes had similar proliferation inhibition effect compared with free DOX. Definitely, the dual-modal SERS-fluorescence complexes for tracing drug delivery and release will have promising prospects on tumor diagnosis and therapy.
基金supported by the National Natural Science Foundation of China(11120101003,11327806)the National Basic Research Program of China(2012CB821403)
文摘We perform an in-plane optical spectroscopy measurement on high quality FeSe single crystals grown by a vapor transport technique. Below the structural transition at Ts - 90 K, the reflectivity spectrum clearly shows a gradual suppression around 400 cm-1 and the conductivity spectrum shows a peak at higher frequency. The energy scale of this gap-like feature is comparable to the width of the band splitting observed by ARPES. The low-frequency conductivity consists of two Drude components and the overall plasma frequency is smaller than that of the FeAs based compounds, suggesting a lower cartier density or stronger correlation effect. The plasma frequency becomes even smaller below Ts which agrees with the very small Fermi energy estimated by other experiments. Similar to iron pnictides, a clear temperature-induced spectral weight transfer is observed for FeSe, being indicative of strong correlation effect.
