The dimension, water content and germination of the seeds from 90 woody species in the lower subtropical forest were analyzed in this study. Out of 90 species, germination analysis was performed in 45 species (in whic...The dimension, water content and germination of the seeds from 90 woody species in the lower subtropical forest were analyzed in this study. Out of 90 species, germination analysis was performed in 45 species (in which there were enough germinating individuals), and the effect of storage of seed and fruit on germination of seed was studied in 41 species (in which there were enough seeds and germinating individuals). Most of the species began to germinate within 60 d. Hypogeal species had longer dormancy than epigeal species. Dormancy of fleshy seeds and seeds in pulpy fruit was also longer than that of dry seeds. There were no significant differences in length of dormancy (LD, days from sowing to germination) between fleshy seeds ripening in summer and those ripening in winter and spring, and between big seeds and small seeds. Seeds in pulpy fruit or fleshy seeds had more germination than the dry seeds ( P <0.05), however, percentage germination was not significantly correlated with water content of fresh seeds. Water loss in the seeds could obviously affect percentage germination, especially during the early three days when the seeds were laid open in air in the laboratory. When water content of the seeds decreased to about 20% (fresh weight basis), percentage germination became very low, this happened when the seeds were laid open in air for 10-14 d. Percentage germination decreased with the length of storing in refrigerator ((4±1) ℃), but it was not markedly affected for one month's storage, with a decrease by 8.3% in comparison with the fresh seeds, and it was greatly affected by storing for more than three months, with values decreasing by 37%, 63%, and 81% for three months', six months' and 12 months' storage respectively. Difference in percentage germination as well as in LD was not significant for most lots after different storing periods between big seeds and small seeds, between fruit storage and seed storage, and between seeds in pulpy fruits or fleshy seeds and dry seeds.展开更多
To investigate the relationship between structure and function of the deferens ducts in the Chinese rat snake (Zaocys dhumnades), morphological changes within an annual cycle were observed by routine histological te...To investigate the relationship between structure and function of the deferens ducts in the Chinese rat snake (Zaocys dhumnades), morphological changes within an annual cycle were observed by routine histological techniques. Also, the correlation of androgen receptor (AR), estrogen receptor (ER), progesterone receptor (PR) and aromatase (Ar) expressions in the vas deferens and testis were studied immunohistochemically. To confh'm that the sperm and the spherical structure existed in deferens ducts, we also used routine histological technique observed deferens ducts in the Striped-tailed rat-snake (Elaphe taeniura), Red-banded snake (Dinodon rufozonatum), and Tiger-spotted neck- troughed snake (Rhabdophis tigrina lateralis). The results showed that the deferens ducts of the Chinese Rat Snake were composed of efferent duct, epididymal duct and vas deferens. Efferent duct contained sperm from August-October, and the sperm were observed in the epididymal duct from August-the following January. Throughout the year (except July) a large number of sperm were present in the vas deferens where a previously unreported spherical structure formed by spermatids was observed, which showed no significant differences in the IOD values of AR-, ER-, PR- and Ar- immunoreactivities. Since the spermatids in the spherical structure were undergoing spermatogenesis and this phenomenon also existed in the Striped-tailed rat-snake and Red-banded snake, the term, seminiferous spherule, was named for this spherical structure This study demonstrated that the testis was the main site for snake spermiogenesis, and the seminiferous spherule in vas deferens was the other Both the epididymis and vas deferens stored sperm; however, the vas deferens was the main organ for sperm storage.展开更多
A novel flash memory cell with stacked structure (Si substrate/SiGe quantum dots/tunneling oxide/polySi floating gate) is proposed and demonstrated to achieve enhanced F-N tunneling for both programming and erasing....A novel flash memory cell with stacked structure (Si substrate/SiGe quantum dots/tunneling oxide/polySi floating gate) is proposed and demonstrated to achieve enhanced F-N tunneling for both programming and erasing. Simulation results indicate the new structure provides high speed and reliability. Experimental results show that the operation voltage can be as much as 4V less than that of conventional full F-N tunneling NAND memory cells. Memory cells with the proposed structure can achieve higher speed, lower voltage, and higher reliability.展开更多
A storage and emission functional material of [Ca24Al28O64]^4+·(Cl^-)3.80(O^2-)0.10 (C12A7-Cl^-), was prepared by the solid-state reactions of CaCO3, γ-Al2O3, and CaCl2 in Cl2/Ar mixture atmosphere. The a...A storage and emission functional material of [Ca24Al28O64]^4+·(Cl^-)3.80(O^2-)0.10 (C12A7-Cl^-), was prepared by the solid-state reactions of CaCO3, γ-Al2O3, and CaCl2 in Cl2/Ar mixture atmosphere. The anionic species stored in the C12A7-Cl^- material were dominated by Cl^-, about (2.21±0.24) × 10^21 cm^-3, accompanied by a small amount of O^2-, O^-, and O2^-, measured via ion chromatography, electron paramagnetic resonance, and raman spectra measurements. These results also corroborate identification of time-of-flight mass spectroscopy--the anionic species emitted from the C12A7-Cl^- surface were dominated by the Cl^- (about 90%) together with a small amount of O^- and electrons. The structure and morphological alterations of the material were investigated via X-ray diffraction and field emission scanning electron microscope, respectively.展开更多
Mg-based Mg-TiO2 composite powder was prepared by arc plasma evaporation of the Mg+5%TiO2 mixture followed by passivation in air. ICP, XRD and SEM techniques were used to characterize the composition, phase component...Mg-based Mg-TiO2 composite powder was prepared by arc plasma evaporation of the Mg+5%TiO2 mixture followed by passivation in air. ICP, XRD and SEM techniques were used to characterize the composition, phase components and microstructure of the composite powder. The hydrogen sorption properties of the composite powder were investigated by DSC and PCT techniques. According to the data from PCT measurements, the hydrogenation enthalpy and entropy changes of the composite powder are calculated to be-71.5 kJ/mol and-130.1 J/(K·mol), respectively. Besides, the hydrogenation activation energy is determined to be 77.2 kJ/ mol. The results indicate that TiO2 added into Mg by arc plasma method can act as a catalyst to improve the hydrogen sorption kinetic properties of Mg.展开更多
Multi-wave exploration is an effective means for improving precision in the exploration and development of complex oil and gas reservoirs that are dense and have low permeability. However, convened wave data is charac...Multi-wave exploration is an effective means for improving precision in the exploration and development of complex oil and gas reservoirs that are dense and have low permeability. However, convened wave data is characterized by a low signal-to-noise ratio and low resolution, because the conventional deconvolution technology is easily affected by the frequency range limits, and there is limited scope for improving its resolution. The spectral inversion techniques is used to identify λ/8 thin layers and its breakthrough regarding band range limits has greatly improved the seismic resolution. The difficulty associated with this technology is how to use the stable inversion algorithm to obtain a high-precision reflection coefficient, and then to use this reflection coefficient to reconstruct broadband data for processing. In this paper, we focus on how to improve the vertical resolution of the converted PS-wave for multi-wave data processing. Based on previous research, we propose a least squares inversion algorithm with a total variation constraint, in which we uses the total variance as a priori information to solve under-determined problems, thereby improving the accuracy and stability of the inversion. Here, we simulate the Gaussian fitting amplitude spectrum to obtain broadband wavelet data, which we then process to obtain a higher resolution converted wave. We successfully apply the proposed inversion technology in the processing of high-resolution data from the Penglai region to obtain higher resolution convened wave data, which we then verify in a theoretical test. Improving the resolution of converted PS-wave data will provide more accurate data for subsequent velocity inversion and the extraction of reservoir reflection information.展开更多
We provides a novel approach to generate low-temperature atomic oxygen anions (O-) emission using the cesium oxide-doped 12CaO.7Al2O3 (Cs2O-doped C12A7). The maximal emission intensity of O- from the Cs2O-doped C1...We provides a novel approach to generate low-temperature atomic oxygen anions (O-) emission using the cesium oxide-doped 12CaO.7Al2O3 (Cs2O-doped C12A7). The maximal emission intensity of O- from the Cs2O-doped C12A7 at 700℃ and 800 V/cm reached about 0.54μA/cm2, which was about two times as strong as that from the un-doped C12A7 (0.23 μA/cm2) under the same condition. The initiative temperature of the O- emission from the Cs2O-doped C12A7 was about 500 ℃, which was also much lower than the initiative temperature from the un-doped C12A7 (570 ℃) in the given field of 800 V/cm. High pure O- emission close to 100% could be obtained from the Cs2O-doped C12A7 under the lower temperature (〈550℃). The emission features of the Cs2O-doped C12A7, including the emission distribution, temperature effect, and emission branching ratio have been investigated in detail and compared with the un-doped C12A7. The structure and storage characteristics of the resulting material were also investigated via X-ray diffraction and electron paramagnetic resonance. It was found that doping Cs2Oto C12A7 will lower the initiative emission temperature and enhance the emission intensity展开更多
A new ROMless twiddle factor generator for radix-2 1024-point FFT is proposed.It consists of several simple logic units and each of them synthesizes some data,which will be used to compose the twiddle factors.The powe...A new ROMless twiddle factor generator for radix-2 1024-point FFT is proposed.It consists of several simple logic units and each of them synthesizes some data,which will be used to compose the twiddle factors.The power analysis with Synopsys Power Compiler shows that it consumes about 2mW with TSMC 0.25μm CMOS process at 50MHz.This twiddle factor generator is designed for the low power applications,especially for the mobile communications and other portable devices...展开更多
Ion conductive membranes(ICMs)are frequently used as separators for energy conversion and storage technologies of fuel cells,flow battery,and hydrogen pump,because of their good ion-selective conduction and low electr...Ion conductive membranes(ICMs)are frequently used as separators for energy conversion and storage technologies of fuel cells,flow battery,and hydrogen pump,because of their good ion-selective conduction and low electronic conductivity.Firstly,this feature article reviews the recent studies on the development of new nonfluorinated ICMs with low cost and their macro/micro-structure control.In general,these new nonfluorinated ICMs have lower conductivity than commercial perfluorinated ones,due to their poor ion transport channels.Increasing ion exchange capacity(IEC)would create more continuous hydrophilic channels,thus enhancing the conductivity.However,high IEC also expands the overall hydrophilic domains,weakens the interaction between polymer chains,enhances the mobility of polymer chains,and eventually induces larger swelling.The micro-scale expansion and macro-scale swelling of the ICMs with high IEC could be controlled by limiting the mobility of polymer chains.Based on this strategy,some ef ficient techniques have been developed,including covalent crosslinking,semi-interpenatrating polymer network,and blending.Secondly,this review introduces the optimization of macro/microstructure of both perfluorinated and nonfluorinated ICMs to improve the performance.Macro-scale multilayer composite is an ef ficient way to enhance the mechanical strength and the dimensional stability of the ICMs,and could also decrease the content of per fluorosulfonic acid resin in the membrane,thereby reducing the cost of the perfluorinated ICMs.Long side chain,multiple functionalization,small molecule inducing micro-phase separation,electrospun nano fiber,and organic–inorganic hybrid could construct more ef ficient ion transport channels,improving the ion conductivity of ICMs.展开更多
We study the entanglement of the superconducting charge qubit with the quantized electromagnetic field in a microwave cavity. It can be controlled dynamically by a classical external field threading the SQUID within t...We study the entanglement of the superconducting charge qubit with the quantized electromagnetic field in a microwave cavity. It can be controlled dynamically by a classical external field threading the SQUID within the charge qubit. Utilizing the controllable quantum entanglement, we can demonstrate the dynamic process of the quantum storage of information carried by charge qubit. On the other hand, based on this engineered quantum entanglement, we can also demonstrate a progressive decoherence of charge cubit with quantum jump due to the coupling with the cavity field in quasi-classical state.展开更多
This paper presents an alternative scheme to realize the storage of entangled states for multiple trapped ions including W state, Bell states, and GHZ states even with ions which exchange vibrational energy with a hea...This paper presents an alternative scheme to realize the storage of entangled states for multiple trapped ions including W state, Bell states, and GHZ states even with ions which exchange vibrational energy with a heating surrounding, Our scheme requires that the ions be simultaneously excited by two laser beams with different frequencies. In this scheme the vibrational degrees of freedom are only regarded as intermediate states and the ions exchange energy via the mediation of the vibration of the vibrational mode in coupling processes. The scheme is insensitive to both the initial vibrational state and heating if the system remains in the Lamb Dicke regime. Since the effective Rabi frequency has a small dependence on the vibrational quantum number the heating will have no direct, effect on the internal state evolution.展开更多
Molybdenum disulfide(MoS2)was loaded on biocarbon using waste camellia dregs(CDs)as the carbon source,which was further coated with dopamine hydrochloride to construct biocarbon/MoS2 electrode composites.The electroch...Molybdenum disulfide(MoS2)was loaded on biocarbon using waste camellia dregs(CDs)as the carbon source,which was further coated with dopamine hydrochloride to construct biocarbon/MoS2 electrode composites.The electrochemical lithium storage performance of the composites with different MoS2 contents was investigated.SEM results demonstrated that the composite had a three-dimensional foam-like structure with MoS2 as the interlayer.XRD and HRTEM tests revealed that MoS2 interlayer spacing in the composite was expanded.XPS analysis showed that new Mo—N bonds were formed in the active material.The electrochemical tests showed that the composite with a MoS2 content of 63%had a high initial specific capacity of 1434 mA·h/g at a current density of 100 mA/g.After a long cycle at a high current,it also showed good cycling stability and the capacity retention was nearly 100%.In addition,it had good lithium ion deintercalation ability in the electrochemical kinetics test.展开更多
The emerging two-dimensional MXene-derived quantum dots(MQDs)have garnered considerable research interest owing to their abundant active edge atoms,excellent electrical conductivity,and remarkable optical properties.C...The emerging two-dimensional MXene-derived quantum dots(MQDs)have garnered considerable research interest owing to their abundant active edge atoms,excellent electrical conductivity,and remarkable optical properties.Compared with their two-dimensional(2D)counterpart MXene,MQDs with forceful size and quantum confinement effects exhibit more unparalleled properties and have considerably contributed to the advanced photocatalysis,detection,energy storage,and biomedicine fields.This critical review summarizes the fundamental properties of MQDs in terms of structure,electricity,and optics.The mechanism,characteristics,and comparisons of two typical synthesis strategies(traditional chemical method and novel fluorine-free or chemical-free method)are also presented.Furthermore,the similarities and differences between MQDs and 2D MXenes are introduced in terms of their functional groups,light absorption capacity,energy band structure,and other properties.Moreover,recent advances in the applications of MQD-based materials for energy conversion and storage(ECS)are discussed,including photocatalysis,batteries,and supercapacitors.Finally,current challenges and future opportunities for advancing MQD-based materials in the promising ECS field are presented.展开更多
The adsorption of hydrogen molecule on the external surface of pure 0120 nanocapsule and endohedrallyH2 @C120 complex has been examined using the density functional theory calculations. Several different bonding confi...The adsorption of hydrogen molecule on the external surface of pure 0120 nanocapsule and endohedrallyH2 @C120 complex has been examined using the density functional theory calculations. Several different bonding configu- rations are considered for the hydrogen molecule approaching the outer surface of the considered nanocages. It has been found that the adsorbed H2 molecule bound weakly to the outer surface of the pure C1~0 nanocapsules in agreement with the recent experimental and theoretical results while, it prefers to be adsorbed rather strongly on the side wall of the endohedrally /-/2@C120 complex. The adsorption of a single layer and bi-layer of two tt2 molecules on the most stable states of the considered H2@C120 complex appears to be feasible, although the molecules of the second layer are weakly bound. Furthermore, it is found that the formation of 100% coverage is favorable thermodynamically, which corresponds to about 20% by weight storage of 1-12 molecules. Thus, surprisingly, we arrive at the prediction that the C120 nanocapsules can be implemented as a novel material for energy storage.展开更多
Known as an engineered reservoir due to fluctuations in trap parameter,a classical source of quantum decoherence is considered for a single trapped ion theoretically.For simplicity it is assumed that the fluctuations ...Known as an engineered reservoir due to fluctuations in trap parameter,a classical source of quantum decoherence is considered for a single trapped ion theoretically.For simplicity it is assumed that the fluctuations involved are white noise processes,which enables us to give a simple master equation description of this source of decoherence.Our results show that the decoherence rate depends on the vibrational quantum number in different ways corresponding to the vibrational excitation sideband used there.Besides,this source of decoherence also leads to occurrence of dissipation in the ion system.展开更多
Due to the small volume of goat semen ejaculate, just a few doses of goat semen were produced when the sperm concentration is 100 × 10^/mL. The study was aimed to determine the viability of extended goat semen at...Due to the small volume of goat semen ejaculate, just a few doses of goat semen were produced when the sperm concentration is 100 × 10^/mL. The study was aimed to determine the viability of extended goat semen at refrigerated condition at 5 ℃ using varying sperm concentrations and evaluated if sperm concentration lower than 100 × 10^6/mL would affect the motility, viability and sperm morphology at refrigerated condition. Using an artificial vagina, ejaculated goat semen was collected from goat semen donor aged 1.5 year. Physical evaluation of the collected semen showed an average volume of 0.54 mL, mean pH of 6.8 and a milky white color with thick consistency indicative of high concentration. Fresh goat semen had an initial average of 76% with an average initial sperm concentration of 128 × 10^/mL. The semen was divided into four treatments: sperm concentration of 100× 10^/mL, 75 × 10^/mL, 50 × 10^/mL and 25 × 10^/mL, and were stored at 5 ℃ for a period of 10 d. The semen evaluation was performed for each of the four treatments every other day. Results showed that the sperm concentration of spermatozoa affected the duration of storage based on the sperm motility percentage, viability and morphology of spermatozoa. The extended goat semen with sperm concentration of 25 and 50 million sperm/mL is optimal for storage within 6 d that gave satisfactory percentage motile, viable and morphologically normal spermatozoa.展开更多
In this work, SiO2 nanoplates with opened macroporous structure on carbon layer (C-mSiO2) have been obtained by dissolving and subsequent ingrowing the outer solid SiO2 layer of the aerosol-based C-SiO2 double-shell...In this work, SiO2 nanoplates with opened macroporous structure on carbon layer (C-mSiO2) have been obtained by dissolving and subsequent ingrowing the outer solid SiO2 layer of the aerosol-based C-SiO2 double-shell hollow spheres. Subsequently, triple-shell C-mSiO2-C hollow spheres were successfully prepared after coating the C- mSiO2 templates by the carbon layer from the carbonization of sucrose. When being applied as the anode material fur lithium-ion batteries, the C-mSiO2-C triple-shell hollow spheres deliver a high capacity of 501 mA. h.g- 1 after 100 cycles at 500 mA.g-1 (based on the total mass of silica and the two carbon shells), which is higher than those of C-mSiO2 (391 mA.h.g 1) spheres with an outer porous SiO2 layer, C-SiO2-C (370 mA-h.g-1) hollow spheres with a middle solid Si02 layer, and C-SiO2 (319.8 mA·h-g-1) spheres with an outer solid SiO2 layer. In addition, the battery still delivers a high capacity of 403 mA· h· g- 1 at a current density of 1000 mA· g- 1 after 400 cycles. The good electrochemical performance can be attributed to the high surface area (246.7 m2·g- 1 ) and pore volume (0.441 cm3· g-1) of the anode materials, as well as the unique structure of the outer and inner carbon layer which not only enhances electrical conductivity, structural stability, but buffers volume change of the intermediate SiO2 layer during repeated charge-discharge processes. Furthermore, the SiO2 nanoplates with opened macroporous structure facilitate the electrolyte transport and electrochemical reaction.展开更多
Silver nanoparticles were obtained by reduction method. Various techniques, such as UV-Vis spectroscopy, transmission electron microscopy (TEM) and light-scattering spectroscopy, were used to characterize nanopartic...Silver nanoparticles were obtained by reduction method. Various techniques, such as UV-Vis spectroscopy, transmission electron microscopy (TEM) and light-scattering spectroscopy, were used to characterize nanoparticles. Sodium borohydride or sodium citrate was adopted as reduction regent, and polyvinyl alcohol or polyethylene glycol was adopted as stabilizing regent. An experimental condition was studied in detail. After the water was eliminated, the silver nanoparticle was fixed in the solid polymer. The silver nanoparticle in polymer could be re-dissolved in water. It was found that light scattering characteristic of silver nanoparticle storied in polymer was not changed. A new method of storing silver nanoparticles in solid polymer was given in this paper.展开更多
The experimental large fluctuation in odd-even differences in moments ofinertia of deformed actinide nuclei is investigated using the particle-number conserving (PNC)method for treating the cranked shell model with mo...The experimental large fluctuation in odd-even differences in moments ofinertia of deformed actinide nuclei is investigated using the particle-number conserving (PNC)method for treating the cranked shell model with monopole and quadrupole pairing interactions. PNCcalculations show that the large odd-even difference in moments of inertia mainly comes from theinterference contributions j(μv) from particles in high j intruder orbitals μ and v quite near theFermi surface, which have no counterpart in the BCS formalism. The effective monopole andquadrupole pairing interaction strengths are determined to fit the experimental odd-even differencesin binding energies and bandhead moments of inertia. The experimental results for the variation ofmoments of inertia with rotational frequency ω are reproduced well by the PNC calculation. Thenearly identical experimental moments of inertia between ~(236)U(gsb) and ~(238)U(gsb) at lowfrequencies hω ≤ 0.20 MeV are also reproduced quite well.展开更多
文摘The dimension, water content and germination of the seeds from 90 woody species in the lower subtropical forest were analyzed in this study. Out of 90 species, germination analysis was performed in 45 species (in which there were enough germinating individuals), and the effect of storage of seed and fruit on germination of seed was studied in 41 species (in which there were enough seeds and germinating individuals). Most of the species began to germinate within 60 d. Hypogeal species had longer dormancy than epigeal species. Dormancy of fleshy seeds and seeds in pulpy fruit was also longer than that of dry seeds. There were no significant differences in length of dormancy (LD, days from sowing to germination) between fleshy seeds ripening in summer and those ripening in winter and spring, and between big seeds and small seeds. Seeds in pulpy fruit or fleshy seeds had more germination than the dry seeds ( P <0.05), however, percentage germination was not significantly correlated with water content of fresh seeds. Water loss in the seeds could obviously affect percentage germination, especially during the early three days when the seeds were laid open in air in the laboratory. When water content of the seeds decreased to about 20% (fresh weight basis), percentage germination became very low, this happened when the seeds were laid open in air for 10-14 d. Percentage germination decreased with the length of storing in refrigerator ((4±1) ℃), but it was not markedly affected for one month's storage, with a decrease by 8.3% in comparison with the fresh seeds, and it was greatly affected by storing for more than three months, with values decreasing by 37%, 63%, and 81% for three months', six months' and 12 months' storage respectively. Difference in percentage germination as well as in LD was not significant for most lots after different storing periods between big seeds and small seeds, between fruit storage and seed storage, and between seeds in pulpy fruits or fleshy seeds and dry seeds.
文摘To investigate the relationship between structure and function of the deferens ducts in the Chinese rat snake (Zaocys dhumnades), morphological changes within an annual cycle were observed by routine histological techniques. Also, the correlation of androgen receptor (AR), estrogen receptor (ER), progesterone receptor (PR) and aromatase (Ar) expressions in the vas deferens and testis were studied immunohistochemically. To confh'm that the sperm and the spherical structure existed in deferens ducts, we also used routine histological technique observed deferens ducts in the Striped-tailed rat-snake (Elaphe taeniura), Red-banded snake (Dinodon rufozonatum), and Tiger-spotted neck- troughed snake (Rhabdophis tigrina lateralis). The results showed that the deferens ducts of the Chinese Rat Snake were composed of efferent duct, epididymal duct and vas deferens. Efferent duct contained sperm from August-October, and the sperm were observed in the epididymal duct from August-the following January. Throughout the year (except July) a large number of sperm were present in the vas deferens where a previously unreported spherical structure formed by spermatids was observed, which showed no significant differences in the IOD values of AR-, ER-, PR- and Ar- immunoreactivities. Since the spermatids in the spherical structure were undergoing spermatogenesis and this phenomenon also existed in the Striped-tailed rat-snake and Red-banded snake, the term, seminiferous spherule, was named for this spherical structure This study demonstrated that the testis was the main site for snake spermiogenesis, and the seminiferous spherule in vas deferens was the other Both the epididymis and vas deferens stored sperm; however, the vas deferens was the main organ for sperm storage.
文摘A novel flash memory cell with stacked structure (Si substrate/SiGe quantum dots/tunneling oxide/polySi floating gate) is proposed and demonstrated to achieve enhanced F-N tunneling for both programming and erasing. Simulation results indicate the new structure provides high speed and reliability. Experimental results show that the operation voltage can be as much as 4V less than that of conventional full F-N tunneling NAND memory cells. Memory cells with the proposed structure can achieve higher speed, lower voltage, and higher reliability.
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China (No.50772107), the National High Tech Research and Development Program (No.2009AA05Z435), and the National Basic Research Program (No.2007CB210206) of Ministry of Science and Technology of China.
文摘A storage and emission functional material of [Ca24Al28O64]^4+·(Cl^-)3.80(O^2-)0.10 (C12A7-Cl^-), was prepared by the solid-state reactions of CaCO3, γ-Al2O3, and CaCl2 in Cl2/Ar mixture atmosphere. The anionic species stored in the C12A7-Cl^- material were dominated by Cl^-, about (2.21±0.24) × 10^21 cm^-3, accompanied by a small amount of O^2-, O^-, and O2^-, measured via ion chromatography, electron paramagnetic resonance, and raman spectra measurements. These results also corroborate identification of time-of-flight mass spectroscopy--the anionic species emitted from the C12A7-Cl^- surface were dominated by the Cl^- (about 90%) together with a small amount of O^- and electrons. The structure and morphological alterations of the material were investigated via X-ray diffraction and field emission scanning electron microscope, respectively.
基金Project(11ZR1417600)supported by Shanghai Natural Science Foundation from Science and Technology Committee of Shanghai,ChinaProject(11PJ1406000)supported by‘Pujiang’Project from the Science and Technology Committee of Shanghai+1 种基金Project(12ZZ017)supported by Shanghai Education Commission,ChinaProject(20100073120007)supported by China Education Commission
文摘Mg-based Mg-TiO2 composite powder was prepared by arc plasma evaporation of the Mg+5%TiO2 mixture followed by passivation in air. ICP, XRD and SEM techniques were used to characterize the composition, phase components and microstructure of the composite powder. The hydrogen sorption properties of the composite powder were investigated by DSC and PCT techniques. According to the data from PCT measurements, the hydrogenation enthalpy and entropy changes of the composite powder are calculated to be-71.5 kJ/mol and-130.1 J/(K·mol), respectively. Besides, the hydrogenation activation energy is determined to be 77.2 kJ/ mol. The results indicate that TiO2 added into Mg by arc plasma method can act as a catalyst to improve the hydrogen sorption kinetic properties of Mg.
基金supported by the China National Petroleum Corporation Scientific research and technology development project(Nos.2013E-38-08)
文摘Multi-wave exploration is an effective means for improving precision in the exploration and development of complex oil and gas reservoirs that are dense and have low permeability. However, convened wave data is characterized by a low signal-to-noise ratio and low resolution, because the conventional deconvolution technology is easily affected by the frequency range limits, and there is limited scope for improving its resolution. The spectral inversion techniques is used to identify λ/8 thin layers and its breakthrough regarding band range limits has greatly improved the seismic resolution. The difficulty associated with this technology is how to use the stable inversion algorithm to obtain a high-precision reflection coefficient, and then to use this reflection coefficient to reconstruct broadband data for processing. In this paper, we focus on how to improve the vertical resolution of the converted PS-wave for multi-wave data processing. Based on previous research, we propose a least squares inversion algorithm with a total variation constraint, in which we uses the total variance as a priori information to solve under-determined problems, thereby improving the accuracy and stability of the inversion. Here, we simulate the Gaussian fitting amplitude spectrum to obtain broadband wavelet data, which we then process to obtain a higher resolution converted wave. We successfully apply the proposed inversion technology in the processing of high-resolution data from the Penglai region to obtain higher resolution convened wave data, which we then verify in a theoretical test. Improving the resolution of converted PS-wave data will provide more accurate data for subsequent velocity inversion and the extraction of reservoir reflection information.
基金This work is supported by the National Natural Science Foundation of China (No.50772107), the National High Tech Research and Development Program (No.2009AA05Z435), and the National Basic Research Program of the Ministry of Science and Technology of China (No.2007CB210206).
文摘We provides a novel approach to generate low-temperature atomic oxygen anions (O-) emission using the cesium oxide-doped 12CaO.7Al2O3 (Cs2O-doped C12A7). The maximal emission intensity of O- from the Cs2O-doped C12A7 at 700℃ and 800 V/cm reached about 0.54μA/cm2, which was about two times as strong as that from the un-doped C12A7 (0.23 μA/cm2) under the same condition. The initiative temperature of the O- emission from the Cs2O-doped C12A7 was about 500 ℃, which was also much lower than the initiative temperature from the un-doped C12A7 (570 ℃) in the given field of 800 V/cm. High pure O- emission close to 100% could be obtained from the Cs2O-doped C12A7 under the lower temperature (〈550℃). The emission features of the Cs2O-doped C12A7, including the emission distribution, temperature effect, and emission branching ratio have been investigated in detail and compared with the un-doped C12A7. The structure and storage characteristics of the resulting material were also investigated via X-ray diffraction and electron paramagnetic resonance. It was found that doping Cs2Oto C12A7 will lower the initiative emission temperature and enhance the emission intensity
文摘A new ROMless twiddle factor generator for radix-2 1024-point FFT is proposed.It consists of several simple logic units and each of them synthesizes some data,which will be used to compose the twiddle factors.The power analysis with Synopsys Power Compiler shows that it consumes about 2mW with TSMC 0.25μm CMOS process at 50MHz.This twiddle factor generator is designed for the low power applications,especially for the mobile communications and other portable devices...
基金Supported by the National Science Fund for Distinguished Young Scholars of China(Grant No.21125628)the Major National Scienti fic Instrument Development Project(Grant No.21527812)+3 种基金the National Natural Science Foundation of China(Grant Nos.21406031 and 21476044)the State Key Laboratory of Fine Chemicals(KF1507)the Fundamental Research Funds for the Central Universities(Grant Nos.DUTPJ14RC(3)003)State Key Laboratory of fine chemicals(Panjin)project(Grant No.JH2014009)
文摘Ion conductive membranes(ICMs)are frequently used as separators for energy conversion and storage technologies of fuel cells,flow battery,and hydrogen pump,because of their good ion-selective conduction and low electronic conductivity.Firstly,this feature article reviews the recent studies on the development of new nonfluorinated ICMs with low cost and their macro/micro-structure control.In general,these new nonfluorinated ICMs have lower conductivity than commercial perfluorinated ones,due to their poor ion transport channels.Increasing ion exchange capacity(IEC)would create more continuous hydrophilic channels,thus enhancing the conductivity.However,high IEC also expands the overall hydrophilic domains,weakens the interaction between polymer chains,enhances the mobility of polymer chains,and eventually induces larger swelling.The micro-scale expansion and macro-scale swelling of the ICMs with high IEC could be controlled by limiting the mobility of polymer chains.Based on this strategy,some ef ficient techniques have been developed,including covalent crosslinking,semi-interpenatrating polymer network,and blending.Secondly,this review introduces the optimization of macro/microstructure of both perfluorinated and nonfluorinated ICMs to improve the performance.Macro-scale multilayer composite is an ef ficient way to enhance the mechanical strength and the dimensional stability of the ICMs,and could also decrease the content of per fluorosulfonic acid resin in the membrane,thereby reducing the cost of the perfluorinated ICMs.Long side chain,multiple functionalization,small molecule inducing micro-phase separation,electrospun nano fiber,and organic–inorganic hybrid could construct more ef ficient ion transport channels,improving the ion conductivity of ICMs.
文摘We study the entanglement of the superconducting charge qubit with the quantized electromagnetic field in a microwave cavity. It can be controlled dynamically by a classical external field threading the SQUID within the charge qubit. Utilizing the controllable quantum entanglement, we can demonstrate the dynamic process of the quantum storage of information carried by charge qubit. On the other hand, based on this engineered quantum entanglement, we can also demonstrate a progressive decoherence of charge cubit with quantum jump due to the coupling with the cavity field in quasi-classical state.
基金The project supported by the State Key Basic Research Development Program of China under Grant No. 20010B309310 and National Natural Science Foundation of China under Grant Nos, 60478029, 90103026, and 10125419,Acknowledgment We would like to thank Prof. Wu Ying for many enlightening discussions.
文摘This paper presents an alternative scheme to realize the storage of entangled states for multiple trapped ions including W state, Bell states, and GHZ states even with ions which exchange vibrational energy with a heating surrounding, Our scheme requires that the ions be simultaneously excited by two laser beams with different frequencies. In this scheme the vibrational degrees of freedom are only regarded as intermediate states and the ions exchange energy via the mediation of the vibration of the vibrational mode in coupling processes. The scheme is insensitive to both the initial vibrational state and heating if the system remains in the Lamb Dicke regime. Since the effective Rabi frequency has a small dependence on the vibrational quantum number the heating will have no direct, effect on the internal state evolution.
基金The authors are grateful for the financial supports from the National Natural Science Foundation of China(50702020,81171461)the Natural Science Foundation of Hunan Province,China(2017JJ2040)the Young Teacher Promotion Fund by Hunan University,China,the Fundamental Research Funds of the Central Universities,China.
文摘Molybdenum disulfide(MoS2)was loaded on biocarbon using waste camellia dregs(CDs)as the carbon source,which was further coated with dopamine hydrochloride to construct biocarbon/MoS2 electrode composites.The electrochemical lithium storage performance of the composites with different MoS2 contents was investigated.SEM results demonstrated that the composite had a three-dimensional foam-like structure with MoS2 as the interlayer.XRD and HRTEM tests revealed that MoS2 interlayer spacing in the composite was expanded.XPS analysis showed that new Mo—N bonds were formed in the active material.The electrochemical tests showed that the composite with a MoS2 content of 63%had a high initial specific capacity of 1434 mA·h/g at a current density of 100 mA/g.After a long cycle at a high current,it also showed good cycling stability and the capacity retention was nearly 100%.In addition,it had good lithium ion deintercalation ability in the electrochemical kinetics test.
文摘The emerging two-dimensional MXene-derived quantum dots(MQDs)have garnered considerable research interest owing to their abundant active edge atoms,excellent electrical conductivity,and remarkable optical properties.Compared with their two-dimensional(2D)counterpart MXene,MQDs with forceful size and quantum confinement effects exhibit more unparalleled properties and have considerably contributed to the advanced photocatalysis,detection,energy storage,and biomedicine fields.This critical review summarizes the fundamental properties of MQDs in terms of structure,electricity,and optics.The mechanism,characteristics,and comparisons of two typical synthesis strategies(traditional chemical method and novel fluorine-free or chemical-free method)are also presented.Furthermore,the similarities and differences between MQDs and 2D MXenes are introduced in terms of their functional groups,light absorption capacity,energy band structure,and other properties.Moreover,recent advances in the applications of MQD-based materials for energy conversion and storage(ECS)are discussed,including photocatalysis,batteries,and supercapacitors.Finally,current challenges and future opportunities for advancing MQD-based materials in the promising ECS field are presented.
文摘The adsorption of hydrogen molecule on the external surface of pure 0120 nanocapsule and endohedrallyH2 @C120 complex has been examined using the density functional theory calculations. Several different bonding configu- rations are considered for the hydrogen molecule approaching the outer surface of the considered nanocages. It has been found that the adsorbed H2 molecule bound weakly to the outer surface of the pure C1~0 nanocapsules in agreement with the recent experimental and theoretical results while, it prefers to be adsorbed rather strongly on the side wall of the endohedrally /-/2@C120 complex. The adsorption of a single layer and bi-layer of two tt2 molecules on the most stable states of the considered H2@C120 complex appears to be feasible, although the molecules of the second layer are weakly bound. Furthermore, it is found that the formation of 100% coverage is favorable thermodynamically, which corresponds to about 20% by weight storage of 1-12 molecules. Thus, surprisingly, we arrive at the prediction that the C120 nanocapsules can be implemented as a novel material for energy storage.
基金Chinese Postdoctoral Fund and National Natural Science Foundation of China
文摘Known as an engineered reservoir due to fluctuations in trap parameter,a classical source of quantum decoherence is considered for a single trapped ion theoretically.For simplicity it is assumed that the fluctuations involved are white noise processes,which enables us to give a simple master equation description of this source of decoherence.Our results show that the decoherence rate depends on the vibrational quantum number in different ways corresponding to the vibrational excitation sideband used there.Besides,this source of decoherence also leads to occurrence of dissipation in the ion system.
文摘Due to the small volume of goat semen ejaculate, just a few doses of goat semen were produced when the sperm concentration is 100 × 10^/mL. The study was aimed to determine the viability of extended goat semen at refrigerated condition at 5 ℃ using varying sperm concentrations and evaluated if sperm concentration lower than 100 × 10^6/mL would affect the motility, viability and sperm morphology at refrigerated condition. Using an artificial vagina, ejaculated goat semen was collected from goat semen donor aged 1.5 year. Physical evaluation of the collected semen showed an average volume of 0.54 mL, mean pH of 6.8 and a milky white color with thick consistency indicative of high concentration. Fresh goat semen had an initial average of 76% with an average initial sperm concentration of 128 × 10^/mL. The semen was divided into four treatments: sperm concentration of 100× 10^/mL, 75 × 10^/mL, 50 × 10^/mL and 25 × 10^/mL, and were stored at 5 ℃ for a period of 10 d. The semen evaluation was performed for each of the four treatments every other day. Results showed that the sperm concentration of spermatozoa affected the duration of storage based on the sperm motility percentage, viability and morphology of spermatozoa. The extended goat semen with sperm concentration of 25 and 50 million sperm/mL is optimal for storage within 6 d that gave satisfactory percentage motile, viable and morphologically normal spermatozoa.
基金Supported by the National Science Funding for Distinguished Young Scholars of China(21125628)National Natural Science Foundation of China(21476044)the Fundamental Research Funds for the Central Universities(DUT15QY08)
文摘In this work, SiO2 nanoplates with opened macroporous structure on carbon layer (C-mSiO2) have been obtained by dissolving and subsequent ingrowing the outer solid SiO2 layer of the aerosol-based C-SiO2 double-shell hollow spheres. Subsequently, triple-shell C-mSiO2-C hollow spheres were successfully prepared after coating the C- mSiO2 templates by the carbon layer from the carbonization of sucrose. When being applied as the anode material fur lithium-ion batteries, the C-mSiO2-C triple-shell hollow spheres deliver a high capacity of 501 mA. h.g- 1 after 100 cycles at 500 mA.g-1 (based on the total mass of silica and the two carbon shells), which is higher than those of C-mSiO2 (391 mA.h.g 1) spheres with an outer porous SiO2 layer, C-SiO2-C (370 mA-h.g-1) hollow spheres with a middle solid Si02 layer, and C-SiO2 (319.8 mA·h-g-1) spheres with an outer solid SiO2 layer. In addition, the battery still delivers a high capacity of 403 mA· h· g- 1 at a current density of 1000 mA· g- 1 after 400 cycles. The good electrochemical performance can be attributed to the high surface area (246.7 m2·g- 1 ) and pore volume (0.441 cm3· g-1) of the anode materials, as well as the unique structure of the outer and inner carbon layer which not only enhances electrical conductivity, structural stability, but buffers volume change of the intermediate SiO2 layer during repeated charge-discharge processes. Furthermore, the SiO2 nanoplates with opened macroporous structure facilitate the electrolyte transport and electrochemical reaction.
文摘Silver nanoparticles were obtained by reduction method. Various techniques, such as UV-Vis spectroscopy, transmission electron microscopy (TEM) and light-scattering spectroscopy, were used to characterize nanoparticles. Sodium borohydride or sodium citrate was adopted as reduction regent, and polyvinyl alcohol or polyethylene glycol was adopted as stabilizing regent. An experimental condition was studied in detail. After the water was eliminated, the silver nanoparticle was fixed in the solid polymer. The silver nanoparticle in polymer could be re-dissolved in water. It was found that light scattering characteristic of silver nanoparticle storied in polymer was not changed. A new method of storing silver nanoparticles in solid polymer was given in this paper.
文摘The experimental large fluctuation in odd-even differences in moments ofinertia of deformed actinide nuclei is investigated using the particle-number conserving (PNC)method for treating the cranked shell model with monopole and quadrupole pairing interactions. PNCcalculations show that the large odd-even difference in moments of inertia mainly comes from theinterference contributions j(μv) from particles in high j intruder orbitals μ and v quite near theFermi surface, which have no counterpart in the BCS formalism. The effective monopole andquadrupole pairing interaction strengths are determined to fit the experimental odd-even differencesin binding energies and bandhead moments of inertia. The experimental results for the variation ofmoments of inertia with rotational frequency ω are reproduced well by the PNC calculation. Thenearly identical experimental moments of inertia between ~(236)U(gsb) and ~(238)U(gsb) at lowfrequencies hω ≤ 0.20 MeV are also reproduced quite well.