恩诺沙星在健康及实验性感染乳房炎奶山羊间的比较药动学

每毫升 10 6菌落形成单位的金黄色葡萄球菌悬液 1ml单侧乳房内接种 ,人工诱发奶山羊乳房炎。 15只泌乳期健康奶山羊 ,按给药途径随机分为 3组 ,采用交叉试验设计 ,分别进行静注、肌注和乳房灌注恩诺沙星 (2 .5mg·kg-1)对健康和人工感染乳房炎的奶山羊进行比较药动学研究。采用HPLC法测定血中恩诺沙星及其代谢产物环丙沙星的浓度 ,用统计矩原理处理药物浓度 时间数据。结果表明 ,实验性乳房炎可以使静注给药后恩诺沙星在奶山羊的消除缓慢 (P <0 .0 5 ) ,消除半衰期 (t1/ 2 β)由 1.32± 0 .2 6h增至 1.77± 0 .12h ;使肌注给药恩诺沙星的吸收、生物转化和代谢均发生显著变化 (P <0 .0 1) ,药 时曲线下面积 (AUC)由 3.0 4mg·h-1·L-1增至 4 .36mg·h-1·L-1,代谢率 (f)由 4 4 .0 6 %降至 2 4 .0 2 % ,环丙沙星的AUC由 1.2 9降至 1.0 1mg·h-1·L-1;使乳房灌注给药恩诺沙星的平均滞留时间 (MRT)由 1.86h增至 2 .2 9h(P <0 .0 5 ) ,f由 4 5 .73%降至 30 .0 6 % (P <0 .0 1)。

《金匮悬解》探微一清胶囊治疗鼻衄的学术渊源

从《金匮悬解》"大黄黄连泻心汤"的应用探讨一清胶囊治疗鼻衄的学术渊源。《金匮悬解》以"相火"立论,认为鼻衄的病机是相火上炎,一清胶囊(原型大黄黄连泻心汤)泻火补气,治疗鼻衄功效卓著。

Improving sintering kinetics and compositional homogeneity of Inconel 625 superalloy open-cell foams made by suspension impregnation method

Open-cell Inconel 625 superalloy foams were prepared by suspension impregnation method which involves replication of pure nickel foam ligaments with a mixed powder suspension and subsequent heat treatments.The objective of the present study is to find a suitable method ensuring complete densification of the superalloy foam ligaments without using low-melting additives and achieving uniform chemical composition at moderate sintering temperatures.Foams prepared using the above methodology were evaluated for the microstructure and compositional variation across the foam ligaments by scanning electron microscopy(SEM)coupled with electron dispersive spectroscopy(EDS).Quasi-static compressive properties of the foams were evaluated.It is shown that if elemental powders of Cr,Mo and Ni are used as additives to the superalloy powder suspension,high ligament density with uniform chemical composition conforming to the Inconel 625 specification is achieved at moderate sintering temperatures.These results are attributed to the formation of low melting eutectics and to acceleration of the diffusion kinetics due to the non-equilibrium thermodynamic conditions created by large compositional gradients in the presence of elemental powders.

Characterization of suspended solids and particle-bound heavy metals in a first flush of highway runoff

To investigate the dynamic characteristics of total suspended solids (TSS) and their particle-bound heavy metals in a first flush, the runoff sampling together with its flow rate measuring was conducted for three rainfall events at outfalls of highway in Shanghai from June to September 2007. Field samples were analyzed to determine the concentrations of TSS and particle-bound heavy metals, such as Zn, Pb, and Cu. Results show that the wash off behavior of TSS under varying runoff rate condition can be explained by different antecedent dry weather period (ADWP). Contribution of fine fraction (<45 μm) to TSS was generally higher than that of coarse fraction (>45 μm). When the runoff flow increased obviously, a significant contribution of the coarse fraction was observed for a certain rainfall events with long antecedent dry weather condition. The changes of total metals concentration and particle-bound metal concentrations were strongly dependent on the TSS variation. TSS was generally well correlated with most particulate-bound heavy metals. Of the heavy metals, the concentration of Zn was found considerably high and that of Pb was significantly low at North Zhongshan 2 Road, in Shanghai, China, but they are still within the range reported in the literature. Fluctuation of heavy metal contents in the coarse fraction during a first flush period was more significant compared with that in the fine fraction. The results will assist in the development of effective control strategies to minimize heavy metals and solids in highway runoff.

New development of Einstein′s viscose law for powder suspension systems

Through the analysis of the present situation of the rheology of suspension disperse systems, the classical Einstein′s viscosity law was developed into the generalized Einstein′s viscosity law which can be further developed into universalized form, called the universalized Einstein′s viscosity law by introducing modification function f(φ) . Some rational forms of the function f(φ) were discussed according to functional approximation method, and were consequently developed into a few suspension disperse system rheological equations suitable for high particle concentration. These equations all keep good consistence with the models acquired in experiments or other mathematical physics analysis.

Constitutive relationship of ionic polymer-metal composite and static response character of its cantilever setup to voltage

As a new ionic polymer-metal composite(IPMC) for artificial muscle,the mechanical performance parameters and the relationship between the deformation and the electrical parameters of the IPMC were studied. With the digital speckle correlation method,the constitutive relationship of the IPMC was confirmed. With non-contact photography measurement,a cantilever setup was designed to confirm the relationship between the deformation of the IPMC film and the applied voltage. The relationship curve of tip displacement of the IPMC cantilever setup vs the voltage was achieved. The results indicate that the IPMC is isotropic,its elastic modulus is 232 MPa and Poisson ratio is 0.163. The curve achieved from the test of the tip displacement of the IPMC cantilever setup shows that the tip displacement reaches the maximum when the stimulated voltage is 5 V. And the tip displacement descends largely when the frequency of the applied voltage is between 30 mHz and 100 mHz.

84消毒液对不同载体的杀菌效果评价

目的:观察以次氯酸钠为主要杀菌成分的84消毒液分别对金黄色葡萄球菌菌悬液布片载体和金属载体的杀菌效果。方法:采用载体浸泡杀菌试验方法。结果:该消毒剂有效杀菌成分含量为500 mg/L,试验重复三次,当杀菌作用时间为5 min时,对布片载体平均杀灭对数值为2.69,对金属载体平均杀灭对数值为3.78,作用时间为10 min时,对布片载体平均杀灭对数值为5.54,对金属载体平均杀灭对数值为6.64,作用时间为15 min时,对布片载体平均杀灭对数值为5.94,对金属载体平均杀灭对数值为6.64。结论:该消毒剂对不同属性载体具有不同的杀菌效果。

Characterization of Suspended Solids and Heavy Metal Distributions during First Flush in Highway Runoff

Nonpoint source pollution has gradually received attention during stormwater flush in highway runoff. The understanding the pollutant characteristics will be criticat issue to treat these types of pollution. In the present study, two monitoring stations were selected to measure hydrology and to take sampling during first flushing events at the Zhong-Shan freeway and East-West expressway in the Miaoli County, Taiwan. The results of monitoring stations in 2007 storm events found that normally the peak concentrations of total suspended solids （TSS） and heavy metals occurred at the initial stormwater and then the concentrations decreased when the measured time elapsed. The highest and lowest heavy metal concentrations were Fe and Ni, respectively, during the stormwater. Particle size distribution （PSD） mostly ranged from 12μm and 96 μm at two measured sites. The event mean concentrations （EMCs） and loadings of TSS and heavy metals were also correlated with total runoff and total rainfall.

宋代的书法辨伪及其学术意蕴

书法之辨伪,主要是对传世书法遗迹真伪优劣的鉴别,不同于古典文献学上的辨伪~1。书法上之辨伪,源于古人有作伪书的风气。据虞龢《论书表》记载,时人因'悬金招买,不计贵贱'的诱惑就有伪作二王书迹的事实。梁武帝与陶弘景《论书启》中也多次言及王羲之书法真伪难辨的问题。这种情况,隋唐以来更加明显和突出。据《唐朝叙书录》记载,唐太宗尝以金帛购求王羲之书迹,所得虽多,然莫能辨其真伪。张怀瓘直以'滥吹之事'喻书法之作伪~2,举'张翼及僧惠式效右军,时人不能辨'等事为证。

Dual-metal precursors for the universal growth of non-layered 2D transition metal chalcogenides with ordered cation vacancies

Two-dimensional(2D)transition metal chalcogenides(TMCs)are promising for nanoelectronics and energy applications.Among them,the emerging non-layered TMCs are unique due to their unsaturated dangling bonds on the surface and strong intralayer and interlayer bonding.However,the synthesis of non-layered 2D TMCs is challenging and this has made it difficult to study their structures and properties at thin thickness limit.Here,we develop a universal dual-metal precursors method to grow non-layered TMCs in which a mixture of a metal and its chloride serves as the metal source.Taking hexagonal Fe_(1-x)S as an example,the thickness of the Fe_(1-x)S flakes is down to 3 nm with a lateral size of over 100 μm.Importantly,we find ordered cation Fe vacancies in Fe_(1-x)S,which is distinct from layered TMCs like MoS_(2) where anion vacancies are commonly observed.Low-temperature transport measurements and theoretical calculations show that 2D Fe_(1-x)S is a stable semiconductor with a narrow bandgap of60 meV.In addition to Fe_(1-x)S,the method is universal in growing various non-layered 2D TMCs containing ordered cation vacancies,including Fe_(1-x)Se,Co_(1-x)S,Cr_(1-x)S,and V_(1-x)S.This work paves the way to grow and exploit properties of non-layered materials at 2D thickness limit.

Geometric optimization of electrostatic fields for stable levitation of metallic materials

Experimental and computational methods are used to optimize the electrostatic field for levitating metallic materials.The calculated launch voltage increases linearly with the distance between top and bottom electrodes.The combination of a larger top electrode diameter with a smaller bottom diameter may enhance the levitation ability because the electric field intensity near the levitated sample is strengthened.Top convex and bottom concave electrodes can guarantee good levitation stability but decrease the levitation force.The design of bottom electrode is crucial to attain not only a stable levitation state but also a higher levitation capability.As a measure characterizing the intrinsic levitation ability of various materials,the product of density and diameter of levitated samples can be used to determine the launch voltage for counteracting gravity according to a power relationship.

Evidence for structural phase transitions and large effective band gaps in quasi-metallic ultra-clean suspended carbon nanotubes

We report evidence for a structural phase transition in individual suspended metallic carbon nanotubes by examining their Raman spectra and electron trans- port under electrostatic gate potentials. The current-gate voltage characteristics reveal anomalously large quasi-metallic band gaps as high as 240 meV, the largest reported to date. For nanotubes with band gaps larger than 200 meV, we observe a pronounced M-shape profile in the gate dependence of the 2D band （or G＇ band） Raman frequency. The pronounced dip （or softening） of the phonon mode near zero gate voltage can be attributed to a structural phase transition （SPT） that occurs at the charge neutrality point （CNP）. The 2D band Raman intensity also changes abruptly near the CNP, providing further evidence for a change in the lattice symmetry and a possible SPT. Pronounced non-adiabatic effects are observed in the gate dependence of the G band Raman mode, however, this behavior deviates from non-adiabatic theory near the CNP. For nanotubes with band gaps larger than 200 meV, non-adiabatic effects should be largely suppressed, which is not observed experimentally. This data suggests that these large effective band gaps are primarily caused by a SPT to an insulating state, which causes the large modulation observed in the conductance around the CNP. Possible mechanisms for this SPT are discussed, including electron-electron （e.g., Mott） and electron-phonon （e.g., Peierls） driven transitions.