In order to identify the potential nephrotoxic compounds in traditional Chinese medicine Lithospermum erythrorhizon,it was separated into serial fractions according to their polarities.An in vitro method was utilized ...In order to identify the potential nephrotoxic compounds in traditional Chinese medicine Lithospermum erythrorhizon,it was separated into serial fractions according to their polarities.An in vitro method was utilized to determine the nephrotoxicity of these fractions with the help of fluorescence image analysis.As a result,the primary fraction A05 and its secondary fractions C06 "C09 and C12 "C14 were found to have significant toxicity to LLC-PK1 cell line,as determined by the survive rate less than 20% after they were treated with these fractions.These potential nephrotoxic fractions were further analyzed by multistage and high resolution mass spectrometry.The main compounds in these fractions were tentatively identified to be acetylshikonin,isobutyrylshikonin,β,β'-dimethyla-cryloylshikonin,and isovalerylshikonin,which may bring nephrotoxicity.展开更多
We can make mistakes at any age.Somemistakes we make are about money.But mostmistakes are about people.“When I got thatjob,did Jim really feel good about it as afriend?Or is he envious(嫉妒)of my luck?”“And Paul—W...We can make mistakes at any age.Somemistakes we make are about money.But mostmistakes are about people.“When I got thatjob,did Jim really feel good about it as afriend?Or is he envious(嫉妒)of my luck?”“And Paul—Why didn't I find that he wasfriendly just because I had a car?”When welook back,thinking about these,that can makeus feel bad.But when we look back.it's too late.展开更多
A new sensitive adsorptive voltammetric method was described for the determination of zirconium at a carbon paste electrode (CPE) in the presence of alizarin complexone (ALC). Optimal analytical conditions are: 1.0?0...A new sensitive adsorptive voltammetric method was described for the determination of zirconium at a carbon paste electrode (CPE) in the presence of alizarin complexone (ALC). Optimal analytical conditions are: 1.0?0-6 or 5.0?0-7 mol/L ALC, 0. 20 mol/L HAC-NaAc (pH 4.3), accumulation for 60 s at 0 V (vs. SCE), and linear scanning from 0 V to 1.0 V at 250 mV/s. The peak potential of the complex is at 0.81 V. By using a model JP-303 polarographic analyzer, 2.0?0-10 mol/L (S/N=3) zirconium can be detected with a 90 s accumulation, when the 2nd-order derivative linear sweep technique is used, and the linear range is 6.0?0-10-2.0?0-8 mol/L (5.0?0-7 mol/L ALC) and 2.0?0-8-2.0?0-7 mol/L (1.0?0-6 mol/L ALC), respectively. The developed method was applied to the determination of trace zirconium in the ore samples with satisfactory results.展开更多
From the point of view of approximate symmetry, the modified Korteweg-de Vries-Burgers (mKdV-Burgers) equation with weak dissipation is investigated. The symmetry of a system of the corresponding partial differentia...From the point of view of approximate symmetry, the modified Korteweg-de Vries-Burgers (mKdV-Burgers) equation with weak dissipation is investigated. The symmetry of a system of the corresponding partial differential equations which approximate the perturbed mKdV-Burgers equation is constructed and the corresponding general approximate symmetry reduction is derived; thereby infinite series solutions and general formulae can be obtained. The obtained result shows that the zero-order similarity solution to the mKdV-Burgers equation satisfies the Painleve II equation. Also, at the level of travelling wave reduction, the general solution formulae are given for any travelling wave solution of an unperturbed mKdV equation. As an illustrative example, when the zero-order tanh profile solution is chosen as an initial approximate solution, physically approximate similarity solutions are obtained recursively under the appropriate choice of parameters occurring during computation.展开更多
Tricalcium phosphate Anhydrous Powder typically contains less than 10 ppm (mg/Kg) (w/w) manganese. This level can be determined utilizing Flame Atomic Absorption Spectrometer (AAS) and standard based on known standard...Tricalcium phosphate Anhydrous Powder typically contains less than 10 ppm (mg/Kg) (w/w) manganese. This level can be determined utilizing Flame Atomic Absorption Spectrometer (AAS) and standard based on known standards. A number of analytical methods are presently used for the analysis of metals in the biochemical. The instrumental techniques available are Inductively Coupled Plasma (ICP/MS), X-Ray Fluorescence, UV-VIS Spectrophotometry, and Atomic Absorption Spectrometry. Flame AA has gained widespread acceptance as an analytical technique and is used for many applications. In this study, we have determined the amount of manganese metal present in Tricalcium Phosphate (TCP) using Flame Atomic Absorption Spectrophotometer. The method has high precision and accuracy. The percent recovery was found to be 99.8% for spiked sample. The results meet the requirement.展开更多
A multi-try counter-meshing gears stronglink based on micro electromechanical system (MEMS) technology is introduced, including research, design, couple and fabrication of unique signal (UQS) for some specified fi...A multi-try counter-meshing gears stronglink based on micro electromechanical system (MEMS) technology is introduced, including research, design, couple and fabrication of unique signal (UQS) for some specified fields of information security. The stronglink consists of two groups of metal counter-meshing gears, two pawl/ratchet mechanisms, two driving micromotors and two resetting micromotors. The resetting micromotors make counter-meshing gears withdraw by raising pawls so that the interfered counter-meshing gears will be relieved. The energy-coupling element is a photoelectric sensor with a circular notched plate. The counter-meshing mechanism is fabricated using the ultraviolet-lithographie~ galvanoformung and abformung (UV-LiGA) process and a precision mechanical technique. The stronglink can be tried several times if the correct resetting code is known.展开更多
下面各句看似简单,但你不妨译译,看是否译得正确。1.“Do you know the distance between San Francisco and New York?”“Beats me.”2.I am big on ice cream.3.I don’t buy your story.4.He was on the carpet for arriving late a...下面各句看似简单,但你不妨译译,看是否译得正确。1.“Do you know the distance between San Francisco and New York?”“Beats me.”2.I am big on ice cream.3.I don’t buy your story.4.He was on the carpet for arriving late at work.5.This is a cock and bull story.展开更多
The tris[(2-methyl-2-phenyl)propyl](2,4-dinitro-phenolato)tin was synthesized by the reaction of bis[tri(2-methyl-2-phenyl)propyltin] oxide with 2,4-dinitrophenol. The compound was characterized by IR, 1H NMR sp...The tris[(2-methyl-2-phenyl)propyl](2,4-dinitro-phenolato)tin was synthesized by the reaction of bis[tri(2-methyl-2-phenyl)propyltin] oxide with 2,4-dinitrophenol. The compound was characterized by IR, 1H NMR spectra and elemental analysis. The crystal structure has been determined by X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/n with a = 0.9649(0), b = 1.0087(8), c = 3.4867(4) nm, β = 90.965(7) , Z = 4, V = 3.3933(7) nm3, Dc = 1.369 Mg·m-3, (MoKa) = 0.796 mm-1, F(000) = 1440, R = 0.0345 and wR = 0.0821. The tin atom has a distorted tetrahedral geometry. The 2D network structure of the complex is formed by hydrogen bonds and π-π effects. The stabilities, orbital energies and composition characteristics of some frontier molecular orbitals of the complexes have been investigated with the aid of G98W software.展开更多
The key to learning a new motor skill—such as playing the piano or mastering a new sport—isn’t necessarily how many hours you spend practising,but the way you practise,according to a 2016 study.Scientists have foun...The key to learning a new motor skill—such as playing the piano or mastering a new sport—isn’t necessarily how many hours you spend practising,but the way you practise,according to a 2016 study.Scientists have found that by subtly varying your training, you can keep your brain more active throughout the learning process, and halve the time it takes to get up to scratch.展开更多
The question was on the mind of every NBA fan last January: Whocould possibly be the next Michael Jordan? Turns out the answer wasn t thenew MJ after all. It was the old Tim Duncan. That s old as in... "old schoo...The question was on the mind of every NBA fan last January: Whocould possibly be the next Michael Jordan? Turns out the answer wasn t thenew MJ after all. It was the old Tim Duncan. That s old as in... "old school." Duncan s game is built on solidfundamentals, hard work and team play. Just as Doctor Naismith intended. Of course, so was Jordan s game. MJ just preferred to play above therim for the first half-dozen years of his career. before he figured out the展开更多
I was not interesting1 in English before. Of course, I was not good at it, and I could hardly keep up with my classmates. But things changed after I met Miss Yu.When I was a new student of Grade Three of the Junior Mi...I was not interesting1 in English before. Of course, I was not good at it, and I could hardly keep up with my classmates. But things changed after I met Miss Yu.When I was a new student of Grade Three of the Junior Middle School, Miss Yu taught us English. She was very lovely, and looked more like a schoolgirl than an English teacher.展开更多
基金Supported by the National Key Scientific and Technological Project of China(No.2009ZX09502-012)the Research Fund for the Doctoral Program of Higher Education of China(No.20090101110126)the Zhejiang Province Science and Technology Plan Project,China(No.2008C23065)
文摘In order to identify the potential nephrotoxic compounds in traditional Chinese medicine Lithospermum erythrorhizon,it was separated into serial fractions according to their polarities.An in vitro method was utilized to determine the nephrotoxicity of these fractions with the help of fluorescence image analysis.As a result,the primary fraction A05 and its secondary fractions C06 "C09 and C12 "C14 were found to have significant toxicity to LLC-PK1 cell line,as determined by the survive rate less than 20% after they were treated with these fractions.These potential nephrotoxic fractions were further analyzed by multistage and high resolution mass spectrometry.The main compounds in these fractions were tentatively identified to be acetylshikonin,isobutyrylshikonin,β,β'-dimethyla-cryloylshikonin,and isovalerylshikonin,which may bring nephrotoxicity.
文摘We can make mistakes at any age.Somemistakes we make are about money.But mostmistakes are about people.“When I got thatjob,did Jim really feel good about it as afriend?Or is he envious(嫉妒)of my luck?”“And Paul—Why didn't I find that he wasfriendly just because I had a car?”When welook back,thinking about these,that can makeus feel bad.But when we look back.it's too late.
文摘A new sensitive adsorptive voltammetric method was described for the determination of zirconium at a carbon paste electrode (CPE) in the presence of alizarin complexone (ALC). Optimal analytical conditions are: 1.0?0-6 or 5.0?0-7 mol/L ALC, 0. 20 mol/L HAC-NaAc (pH 4.3), accumulation for 60 s at 0 V (vs. SCE), and linear scanning from 0 V to 1.0 V at 250 mV/s. The peak potential of the complex is at 0.81 V. By using a model JP-303 polarographic analyzer, 2.0?0-10 mol/L (S/N=3) zirconium can be detected with a 90 s accumulation, when the 2nd-order derivative linear sweep technique is used, and the linear range is 6.0?0-10-2.0?0-8 mol/L (5.0?0-7 mol/L ALC) and 2.0?0-8-2.0?0-7 mol/L (1.0?0-6 mol/L ALC), respectively. The developed method was applied to the determination of trace zirconium in the ore samples with satisfactory results.
基金supported by the National Natural Science Foundations of China(Grant Nos 10735030,10475055,and 90503006)the National Basic Research Program of China(Grant No 2007CB814800)+1 种基金the Science Foundation for Post Doctorate Research from the Ministry of Science and Technology of China(Grant No 20070410727)the Natural Science Basic Research Plan in Shaanxi Province,China(Grant No SJ08A09)
文摘From the point of view of approximate symmetry, the modified Korteweg-de Vries-Burgers (mKdV-Burgers) equation with weak dissipation is investigated. The symmetry of a system of the corresponding partial differential equations which approximate the perturbed mKdV-Burgers equation is constructed and the corresponding general approximate symmetry reduction is derived; thereby infinite series solutions and general formulae can be obtained. The obtained result shows that the zero-order similarity solution to the mKdV-Burgers equation satisfies the Painleve II equation. Also, at the level of travelling wave reduction, the general solution formulae are given for any travelling wave solution of an unperturbed mKdV equation. As an illustrative example, when the zero-order tanh profile solution is chosen as an initial approximate solution, physically approximate similarity solutions are obtained recursively under the appropriate choice of parameters occurring during computation.
文摘Tricalcium phosphate Anhydrous Powder typically contains less than 10 ppm (mg/Kg) (w/w) manganese. This level can be determined utilizing Flame Atomic Absorption Spectrometer (AAS) and standard based on known standards. A number of analytical methods are presently used for the analysis of metals in the biochemical. The instrumental techniques available are Inductively Coupled Plasma (ICP/MS), X-Ray Fluorescence, UV-VIS Spectrophotometry, and Atomic Absorption Spectrometry. Flame AA has gained widespread acceptance as an analytical technique and is used for many applications. In this study, we have determined the amount of manganese metal present in Tricalcium Phosphate (TCP) using Flame Atomic Absorption Spectrophotometer. The method has high precision and accuracy. The percent recovery was found to be 99.8% for spiked sample. The results meet the requirement.
基金the High-Technology Research and Development Program of China (Grant No.863-2003AA404210,the second phase 863-2005AA404250,863-2003AA404210 and the third phase 863-2006AA01Z443)
文摘A multi-try counter-meshing gears stronglink based on micro electromechanical system (MEMS) technology is introduced, including research, design, couple and fabrication of unique signal (UQS) for some specified fields of information security. The stronglink consists of two groups of metal counter-meshing gears, two pawl/ratchet mechanisms, two driving micromotors and two resetting micromotors. The resetting micromotors make counter-meshing gears withdraw by raising pawls so that the interfered counter-meshing gears will be relieved. The energy-coupling element is a photoelectric sensor with a circular notched plate. The counter-meshing mechanism is fabricated using the ultraviolet-lithographie~ galvanoformung and abformung (UV-LiGA) process and a precision mechanical technique. The stronglink can be tried several times if the correct resetting code is known.
文摘下面各句看似简单,但你不妨译译,看是否译得正确。1.“Do you know the distance between San Francisco and New York?”“Beats me.”2.I am big on ice cream.3.I don’t buy your story.4.He was on the carpet for arriving late at work.5.This is a cock and bull story.
基金the Natural Science Foundation of Hunan Province (No. 11JJ3021)the Innovation Platform Open fund of Hunan Provincial Education Department (No.09K099 and No. 10K010) and a key project (No. 10A014)+3 种基金the Hunan Provincial Scientific Program (No.2010JT4041)the open fund of the Key Laboratory of Functional Organometallic Materials of Colleges of Hunan Province (No.10K02)Hengyang Municipal Scientific Program (2011KG56)the Youth Program of Hengyang Normal University (No. 11A28)
文摘The tris[(2-methyl-2-phenyl)propyl](2,4-dinitro-phenolato)tin was synthesized by the reaction of bis[tri(2-methyl-2-phenyl)propyltin] oxide with 2,4-dinitrophenol. The compound was characterized by IR, 1H NMR spectra and elemental analysis. The crystal structure has been determined by X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/n with a = 0.9649(0), b = 1.0087(8), c = 3.4867(4) nm, β = 90.965(7) , Z = 4, V = 3.3933(7) nm3, Dc = 1.369 Mg·m-3, (MoKa) = 0.796 mm-1, F(000) = 1440, R = 0.0345 and wR = 0.0821. The tin atom has a distorted tetrahedral geometry. The 2D network structure of the complex is formed by hydrogen bonds and π-π effects. The stabilities, orbital energies and composition characteristics of some frontier molecular orbitals of the complexes have been investigated with the aid of G98W software.
文摘The key to learning a new motor skill—such as playing the piano or mastering a new sport—isn’t necessarily how many hours you spend practising,but the way you practise,according to a 2016 study.Scientists have found that by subtly varying your training, you can keep your brain more active throughout the learning process, and halve the time it takes to get up to scratch.
文摘The question was on the mind of every NBA fan last January: Whocould possibly be the next Michael Jordan? Turns out the answer wasn t thenew MJ after all. It was the old Tim Duncan. That s old as in... "old school." Duncan s game is built on solidfundamentals, hard work and team play. Just as Doctor Naismith intended. Of course, so was Jordan s game. MJ just preferred to play above therim for the first half-dozen years of his career. before he figured out the
文摘I was not interesting1 in English before. Of course, I was not good at it, and I could hardly keep up with my classmates. But things changed after I met Miss Yu.When I was a new student of Grade Three of the Junior Middle School, Miss Yu taught us English. She was very lovely, and looked more like a schoolgirl than an English teacher.