Thermal Decomposition of Ammonium 3-Nitro-1,2,4-triazol-5-onate Monohydrate

The thermal decomposition of ammonium 3-nitro-1,2,4-triazol-5-onate monohydrate[NH4（NTO）·H2O] was studied by means of thermal analysis-MS coupling and the combination technique of in situ thermolysis cell with rapid-scan Fourier transform infrared spectroscopy. The results show that there are two endothermic steps and one exothermic step in the decomposition process of NH4（NTO）·H2O. The detected gas products consist of NH3, H2O, N2, CO2, CO, and NO2.

Thermodynamic properties of metamizol monohydrate in pure and binary solvents at temperatures from(283.15 to 313.15) K

The thermodynamic properties of metamizol monohydrate in pure solvents(methanol,ethanol,n-propanol and isopropanol) and two binary mixed solvent systems including(methanol+ethanol) and(methanol+isopropanol) were measured from 283.15 K to 313.15 K by gravimetric method under atmospheric pressure thought as 0.1 MPa.The modi fied Apelblat equation,the CNIBS/R-K equation,the Hybrid model and the NRTL model were used to correlate the solubility of metamizol monohydrate,respectively.The results show that the solubility of metamizol monohydrate in all the tested solvents increases with the rising temperature which means that it has temperature dependence.What's more,the effects of solvent components of the binary solvent mixtures on solubility were discussed,it illustrates that the increasing of the molar fraction of methanol gives the system a greater dissolving power.Furthermore,according to the NRTL model,the enthalpy,the Gibbs energy and the entropy of the mixing process were also obtained and discussed.

Studies on the Mechanism of Primary Nucleation of Ciprofloxacin Hydrochloride Monohydrate

A general expression for the ralationship between induction period and supersaturation was developed based on polynuclear approach.Different mechanism of primary nucleation in solution can be illustrated by the expression.The results of induction period determined by laser scatering method shows that the crystallization of ciprofloxacin hydrochloride monohydrate in water/ethanol or aqueous solution is by the mechanism of primary nucleation followed by one-dimensional diffusion growth,and then one-dimensional continuous or “birth and spread” growth on crystal face. The growth mechanism on the crystal face is affected by temperature and solvent.

Ultrasound assisted crystallization of cephalexin monohydrate:Nucleation mechanism and crystal habit control

With the high-quality requirements for cephalexin monohydrate,developing a robust and practical crystallization process to produce cephalexin monohydrate with good crystal habit,appropriate aspect ratio and high bulk density as well as suitable flowability is urgently needed.This research has explored the influence of ultrasound on crystallization of cephalexin monohydrate in terms of nucleation mechanism and crystal habit control.The results of metastable zone width and induction time measurement showed the presence of ultrasound irradiation can narrow the metastable zone and shorten induction time.Cavitation phenomena generated by ultrasound were used to qualitatively explain the mechanism of ultrasound promoting nucleation of cephalexin monohydrate.Furthermore,on the basis of classical nucleation theory and induction time data,a series of nucleation-related parameters(such as crystalliquid interfacial tension,radius of the critical nucleus and etc.)were calculated and showed a decreasing trend under ultrasound irradiation.The diffusion coefficient of the studied system was also determined to increase by 72.73%under ultrasound.The changes in these parameters have quantitatively confirmed the mechanism of ultrasound influence on the nucleation process.In further,the calculated surface entropy factor has confirmed that the growth of cephalexin monohydrate follows continuous growth mechanism under the research conditions of this work.Through the exploration of crystallization conditions,it is found that suitable ultrasonic treatment,seeding,supersaturation control and removal of fine crystals are conducive to improving the quality of cephalexin monohydrate product.Optimizing the crystallization process coupled continuous ultrasound irradiation with fine-crystal dissolution policy has achieved the controllable production of monodisperse cephalexin monohydrate crystal with good performance.

Structure, Growth and Characterization of Ammonium 5-Sulfosalicylic Acid Monohydrate Crystal

Ammonium 5-sulfosalicylic acid monohydrate （NH4·C7H5O6S·H2O, ASSA） was synthesized and optical grade crystal with dimensions of 45ram × 20mm × 18mm was obtained from aqueous solution by the cooling solution method. The crystal structure was confirmed by X-ray single-crystal diffraction method and the empirical composition is C7HIINO7S with formula weight 253.23. The crystal belongs to monoclinic space group P21/c with a = 1 1.884（9）, b = 7.306（5）, c = 12.152（9） A, β = 104.851（13）°, V= 1019.8（13） A3, Z = 4, Dc = 1.649 g/cm3,μ = 0.340 mm-1, F（000） =528, the final R= 0.0307 and wR= 0.0866 for 7494 observed reflections （I〉 2σ（I））, Elemental analysis, 1R and 1H-NMR spectrum were used to characterize the compound. Thermal analysis showed that one coordination water molecule was contained and dehydration temperature of ASSA crystal was 106℃. Optical transmission and fluorescence spectrum revealed that the ASSA crystal exhibited a strong absorption in ultraviolet region with the sharp absorption edge located at 340 nm and a significant blue fluorescent emission band at 442 nm.

Theoretical and Electrochemical Characterization of δ-RuCl2(Nazpy)2: Application to Oxidation of D-Glucose

The heterogenized δ-RuCl2(Nazpy)2 deposited on carbon toray (CT) was studied for the first time as electrochemical catalyst. Before, it was characterized by visible-ultraviolet spectra and theoretically by TDDFT method at B3LYP/Lanl2DZ level. It displayed an MLCT t2geg → π* transition where t2geg due to the structure of Nazpy that considerably reduces energy between d AOs of Ru represents the HOMO of the complex and π* is identified as the LUMO. Electrochemistry study shows two redox ranges in both negative and positive sides of the potential. The positive side that corresponds to the couple RuIV/RuIII of catalyst appears to be active for oxidation of D-glucose in carbonate buffer with a high turnover. Therefore, Keto-2-gluconic and gluconic acids were the two main products obtained with respectively 80% and 17.6% of selectivity. Moreover, a small amount of tartaric and glycol acids coming from the c-c bond cleavage due to non-protection of the anomeric carbon of D-glucose were also observed.

Synthesis,Growth and Spectroscopic Studies of Piperazinium Paranitrophenolate Monohydrate Crystals

A new piperazinium 4-nitro phenolate monohydrate single crystal(PNP)was grown by employing the solution growth technique piperazine and 4-nitrophenol,were the source material used for the growth,acetonitrile is used as solvent.The grown crystal was characterized by Single X-ray analysis and it shows that piperazinium 4-nitrophenol monohydrate crystallizes in the monoclinic space group P2 1/c,with cell parameters a=10.902 5(4),b=6.226 1(3),c=14.031 8(5),and z=4.The lattice parameters of the substances were also determined by using powder diffraction methods.The functional groups are identified by using FTIR spectral analysis.The absorbance of title compound were analyzed using UV-Vis spectra.The thermo analytical properties of the crystal were studied using TG,DTA.

Optical Rotatory Dispersion Measurement of D-Glucose with Fixed Polarizer Analyzer Accessory in Conventional Spectrophotometer

In the sample compartment of a conventional spectrophotometer, mounting of a polarizer before sample and an analyzer behind sample allows the determination of the optical rotatory dispersion of optical active media by measurement of the transmission ratio of crossed and parallel arranged polarizer and analyzer. A formula for the determination of the angle of rotation is derived from the transmission ratio. The arrangement is applied to determine the molar optical rotation of D-glucose in water in the wavelength range from 220 nm to 820 nm.

Synthesis and Crystal Structure of N-[(3aR,4R,4aR,5aS,6S,6aS)-1,3-Dioxo-octahydro-4,6-ethenocyclopropa[f]isoindol-2(1H)-yl]-4-(trifluoromethyl)phenylmethanimine Monohydrate

The crystal structure of the title compound （C19H17F3N2O4, Mr = 394.35） was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group C2/c with a = 28.383（6）, b = 10.355（2）, c = 12.799（3） A, β = 111.74（3）°, V= 3493.8（12） A3, Z = 8, De = 1.499 g,/cm3, λ（MoKα） = 0.71073, F（000） = 1632,μ = 0.127 mm^-1, R = 0.0412 and wR = 0.1019. In the title compound, there exist three intermolecular hydrogen interactions （O（4）...O（1）, 0（4）...0（3） and O（4）...N（1）） between water. The neighboring molecules are linked to each other generating a two-dimensional network structure via the three intermolecular hydrogen bonds and π-π interactions shaped by phen-phen with centroid distance of 4.049 A.

Synthesis and Crystal Structure of 5-Allyl-2,3-dihydro-9-(2-hydroxy-5-oxocyclopent-1-enyl)-cyclopenta[b]chromen-1(9H)-one Monohydrate

The title compound 5-allyl-2,3-dihydro-9-（2-hydroxy-5-oxocyclopent-1-enyl）-cyclopenta[b]chromen-1（9H）-one monohydrate（C20H18O4.H2O,Mr = 340.36） was synthesized and crystallized.It crystallizes in the triclinic system,space group P with a = 8.5840（17）,b = 8.7027（17）,c = 11.561（2）,α = 89.69（3）,β = 74.33（3）,γ = 86.13（3）°,V = 829.6（3）（A°）^3,Z = 2,Dc = 1.363 g/cm^3,MoKa radiation（λ = 0.71073 ）,F（000） = 360,μ = 0.098 mm^-1,the final R = 0.0430 and wR = 0.1008 for 2957 observed reflections with（I 〉 2σ（I））.X-ray analysis reveals that atoms C（1）,C（2）,C（3）,C（4）,C（5） and O（1） on the new pyran ring are coplanar,which is obviously different from the half-chair or boat conformations of other similar compounds.

Anomeric specificity of D-glucose metabolism study in rat and human erythrocytes

The anomeric specificity of D-glucose metabolism in erythrocytes has been since 1985 the matter of extensive investigations reported in about ten publications. The present report aims at providing an integrated review of the major findings on this issue.

Nonlinear Optical Properties and Optical Limiting Measurements of {(1Z)-[4-(Dimethylamino)Phenyl]Methylene} 4-Nitrobenzocarboxy Hydrazone Monohydrate under CW Laser Regime

We report results from the investigation of the nonlinear refractive index and nonlinear absorption coefficient of {(1Z)-[4-(Dimethylamino)phenyl]methylene} 4-nitrobenzocarboxy hydrazone mono-hydrate (DMPM4NBCHM) solution using Z-scan technique with a continuous wave (CW) Argon ion laser. The results show that this type of organic material has a large nonlinear absorption and nonlinear refractive index at 488 nm and 514 nm. The origin of the nonlinear effects was discussed. We demonstrate that the light induced nonlinear refractive index variation, leads to limiting effect. The results indicated that DMPM4NBCHM could be promising candidates for application on nonlinear photonic devices and optical limiters.

Solubilities of 2-Naphthalenesulfonic Acid Monohydrate and Sodium 2-Naphthalenesulfonate in Sulfuric Acid Solution and Their Application for Preparing Sodium 2-Naphthalenesulfonate

The solubilities of 2-naphthalenesulfonic acid monohydrate and sodium 2-naphthalenesulfonate in sulfuric acid solutions were measured at temperatures ranging from 278.15 to 338.15 K by using a dynamic method. The concentration of sulfuric acid solution ranged from 0 to 80wt%,. The solubilities of 2-naphthalenesulfonic acid monohydrate and sodium 2-naphthalenesulfonate increased with temperature, and both of them were the lowest at 70wt %, of sulfuric acid solution(w^0_3 =0.70)while the highest in pure water. The solubility data were correlated by the modified Apelblat equation. Based on the solubility difference between 2-naphthalenesulfonic acid monohydrate and sodium 2-naphthalenesulfonate, a new technique in which sodium sulfate was used to replace sodium sulfite in the neutralization reaction was developed. The suitable mole ratio of H_2O to Na_2SO_4 in the neutralization reaction was 80∶1, and that of 2-naphthalenesulfonic acid monohydrate to Na_2SO_4 was 3.2∶1. The material balance under the suitable mole ratios was given and discussed.

Comparative proteomic analysis of renal tubular epithelial cell injury caused by oxalic acid and calcium oxalate monohydrate

Objective To analyze and identify the differentially expressed proteins in human renal tubular epithelial ceils ( HK-2) after injury caused by oxalic acid and calcium oxalate monohydrate ( COM ) crystal,and to explore the potential role of renal tubular cell injury in kidney stone formation. Methods Normal HK-2 cells

锂电池回收产出的碳酸锂制备单水氢氧化锂工艺分析与探讨

锂元素的回收是电池回收工艺中的关键步骤,目前一般采用湿法浸出技术将有价元素从锂电池黑粉中转移到溶液中,然后经过除杂净化得到精制的硫酸锂溶液,加入碳酸钠制备成工业级碳酸锂或者碳酸锂粗品,再经精制除杂得到碳酸锂产品返回电池生产过程。随着氢氧化锂市场需求的提高,如何将碳酸锂经济高效地转化为氢氧化锂也成为重要环节。针对电池回收产生的工业级碳酸锂转化为氢氧化锂的工艺过程,详细分析了不同工艺路线的原料选择、工艺过程、产品及副产品产出以及能源消耗等关键因素,通过对比不同工艺路线的优劣势,总结出不同企业状态适用的工艺路线,旨在为优化生产流程、提高回收产业链附加值提供有价值的参考。研究结果将有助于指导电池回收企业在选择氢氧化锂生产工艺时作出决策,同时也为盐湖提锂和矿石提锂产生的碳酸锂生产氢氧化锂提供借鉴。

龙泉地区泌尿系结石成分构成特点及碳酸氢钠干预效果分析

目的:分析龙泉地区泌尿系结石成分构成特点及碳酸氢钠干预效果。方法:选取2021年1月1日—2022年12月31日在我院就诊的997例泌尿系结石患者,均进行结石成分分析。将结石负荷大,易复发的患者随机分入对照组和碳酸氢钠干预组,对照组给予呋塞米口服,干预组在对照组基础上予以碳酸氢钠片口服。对比两组的干预效果及复发情况。结果:997份泌尿系结石标本的成分中,以一水草酸钙、二水草酸钙、碳酸磷灰石所占比例较高。结石成分组成中以混合性成分结石为主,其中以一水草酸钙、二水草酸钙、碳酸磷灰石及一水草酸钙、碳酸磷灰石为主。女性患者(36.11%)明显少于男性患者(63.89%),其中六水磷酸铵镁在男性患者中的比例明显低于女性(P<0.05)。合并尿路感染的患者(37.31%)少于未合并患者(62.69%),其中六水磷酸铵镁在合并尿路感染患者中的比例明显高于未合并患者(P<0.05)。997例泌尿系结石患者中,以40~59岁的患病率(64.89%)最高,其次为60~69岁(16.25%)及30~39岁(12.74%)。本研究中结石负荷大、易复发的患者共有768例,随机纳入对照组(376例)和碳酸氢钠干预组(392例)。干预组患者的总有效率为94.64%,明显高于对照组的84.84%(P<0.05);术后随访中,干预组患者的复发率为7.91%,明显低于对照组的15.16%(P<0.05)。结论:龙泉地区的泌尿系结石病患者以混合性成分结石为主,其中以草酸钙及碳酸磷灰石为主,且男性患者多于女性患者,合并尿路感染者少于未合并感染者,30~69岁为结石高发年龄段。另外,采用碳酸氢钠治疗泌尿系结石具有一定的疗效,值得临床推广应用。

HELMHOLTZ FREE ENERGY IN A SYSTEM OF ANISOTROPIC CHAINLIKE MOLECULES AND ITS APPLICATIONS FOR NORMAL MONOHYDRIC ALCOHOLS AND NORMAL ALKANES

1 INTRODUCTIONAfter Prausnitz et al.published the perturbed hard-sphere chain theory(PHCT),manymodified theories have been put forward,such as the perturbed soft-sphere chain theory(PSCT),the perturbed anisotropic chain theory(PACT)and the associated perturbedanisotropic chain theory(APACT).These theories are all concerned with the parameter3c.But,Wertheim in his work proved that the free energy of hard-sphere chain couldbe calculated without 3c.Induced by the work done by Wertheim,Chapman

α-乳糖一水合物太赫兹动力学研究

α-乳糖一水合物是一种重要的水合物,其结合水对乳糖分子结构的影响一直是相关领域的研究热点之一。利用太赫兹时域光谱技术通过设置温度梯度对α-乳糖一水合物进行低温下的太赫兹动力学研究,发现α-乳糖一水合物在1.2 THz、1.3 THz的2个吸收峰随温度变化而红移。为进一步探究其吸收峰的产生机理,基于密度泛函理论对α-乳糖一水合物分别进行了单分子和晶胞理论计算并分析了α-乳糖一水合物的吸收峰振动模式。结果表明,α-乳糖一水合物的吸收峰来源于水分子和乳糖分子间的相互作用以及乳糖分子骨架振动,晶胞计算比单分子计算对于太赫兹波段内振动模式的预测更加准确。

3-甲基-8-喹啉磺酰氯的合成

以硝基苯作为起始原料,经还原后,与2-甲基丙烯醛环合,再与氯磺酸反应制备得到阿加曲班的关键中间体3-甲基-8-喹啉磺酰氯,结构经1H NMR、ESI-MS等确证,并对合成工艺进行了优化。优化条件下,总收率达78.4%(以硝基苯计),纯度达98.6%(HPLC)。制备方法操作简单,反应条件比较温和,使用的起始物料和试剂廉价易得,可用于工业化生产。

氢氧化锂结晶优化研究

单水氢氧化锂作为锂电池的重要原材料,其需求量随着新能源汽车的快速发展而不断增长,同时正极材料、电池厂商等下游企业对于上游工厂生产的单水氢氧化锂的品质要求也在进一步提高。本文从蒸发结晶角度研究了如何优化单水氢氧化锂结晶体结构,探究了溶液浓度、蒸发温度以及搅拌速率对结晶体的影响。实验结果表明改变蒸发条件对于单水氢氧化锂结晶有一定影响,通过选择合适的溶液浓度、蒸发温度和搅拌速率可以改善结晶体的微观形貌、提高粒径均一性。