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Experimental study on high-efficiency polishing for potassium dihydrogen phosphate (KDP) crystal by using

Ziyuan LIU, Hang GAO, Dongming GUO

《机械工程前沿(英文)》 2020年 第15卷 第2期   页码 294-302 doi: 10.1007/s11465-019-0576-4

摘要: A high-efficiency polishing approach using two-phase air–water fluid (TAWF) is proposed to avoid surface contamination and solve the inefficiency of previous water-dissolution polishing techniques for potassium dihydrogen phosphate (KDP) crystal. In the proposed method, controllable deliquescence is implemented without any chemical impurity. The product of deliquescence is then removed by a polishing pad to achieve surface planarization. The mechanism underlying TAWF polishing is analyzed, a special device is built to polish the KDP crystal, and the effect of relative humidity (RH) on polishing performance is studied. The relationship between key parameters of polishing and surface planarization is also investigated. Results show that the polishing performance is improved with increasing RH. However, precisely controlling the RH is extremely difficult during TAWF polishing. Controllable deliquescence can easily be disrupted once the RH fluctuates, which therefore needs to be restricted to a low level to avoid its influence on deliquescence rate. The material removal of TAWF polishing is mainly attributed to the synergistic effect of deliquescence and the polishing pad. Excessive polishing pressure and revolution rate remarkably reduce the life of the polishing pad and the surface quality of the KDP crystal. TAWF polishing using IC-1000 and TEC-168S increase the machining efficiency by 150%, and a smooth surface with a root mean square surface roughness of 5.5 nm is obtained.

关键词: potassium dihydrogen phosphate (KDP) crystal     controllable deliquescence     two-phase air–water fluid     high-efficiency polishing     material removal    

Influences of additives on the crystal habit of potassium chloride

Xiaofu GUO, Junsheng YUAN, Zhiyong JI, Min SU,

《化学科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 78-81 doi: 10.1007/s11705-009-0300-8

摘要: By means of constant control speed cooling crystallization, the influences of four additives, including lead chloride, cadmium chloride, sodium salicylate, and quaternary ammonium salt, on the crystal habit of KCl were investigated. The results show that the crystal habit of KCl is cube without additives, the crystal habit of KCl is ellipsoid-like in the presence of Pb, the crystal habit of KCl is strip in the presence of Cd, and the crystal habit of KCl is cavate cube in the presence of sodium salicylate. X-ray diffractometry analysis reveals that these additives can change the crystal habit of KCl but not its crystal structure.

关键词: cadmium chloride     salicylate     presence     crystallization     diffractometry analysis    

Solvates and polymorphs of clindamycin phosphate: Structural, thermal stability and moisture stability

Junbo Gong, Dejiang Zhang, Yuanyuan Ran, Keke Zhang, Shichao Du

《化学科学与工程前沿(英文)》 2017年 第11卷 第2期   页码 220-230 doi: 10.1007/s11705-017-1624-4

摘要: Clindamycin phosphate (CP), an antibacterial agent, has been reported to form several solid-state forms. The crystal structures of two CP solvates, a dimethyl sulfoxide (DMSO) solvate and a methanol/water solvate (solvate V), have been determined by single crystal X-ray diffraction. The properties and transformations of these forms were characterized by powder X-ray diffraction, Single-crystal X-ray diffraction, differential scanning calorimetry, thermo gravimetric analysis, hot-stage microscopy, and dynamic vapor sorption. Very different hydrogen bonding networks exist among the host-host and host-solvent molecules in the two crystal structures, resulting in different moisture stabilities. The thermal stabilities of the two solvates upon heating and desolvation were also studied. When the temperature was above the boiling point of methanol, solvate V converted to a polymorphic phase after a one step desolvation process, whereas the desolvation temperature of the DMSO solvate was below the boiling point of DMSO. At the relative humidity above 43%, the DMSO solvate transformed to a hydrate at 25 °C. In contrast, solvate V did not transform at any of the humidities studied.

关键词: clindamycin phosphate     solvate     crystal structure     thermal stability     moisture stability    

Effect of potassium carbonate on catalytic synthesis of calcium carbide at moderate temperature

Dejun SHI, Ke QIAO, Zifeng YAN

《化学科学与工程前沿(英文)》 2011年 第5卷 第3期   页码 372-375 doi: 10.1007/s11705-010-0570-1

摘要: Calcium carbide was successfully synthesized by carbothermal reduction of lime with coke at 1973 K for 1.5 h. The effect of potassium carbonate as additive on the composition and morphology of the product was investigated using X-ray diffraction and scanning electron microscope. Addition of potassium carbonate increased the yield of calcium carbide. The sample in the presence of potassium carbonate generated acetylene gas of 168.3 L/kg, which was 10% higher than that in the absence of potassium carbonate. This result confirmed the catalytic effect of potassium carbonate on the synthesis of calcium carbide. A possible mechanism of the above effects was that the additive, which was melted at the reduction temperature, dissolved CaO and so promoted the contact between CaO and carbon, which was essential for the solid-solid reaction to form calcium carbide.

关键词: calcium carbide     synthesis     catalysis    

control and crack-free surface fabrication techniques for ultra-precision fly cutting of large-aperture KDP

F. H. ZHANG, S. F. WANG, C. H. AN, J. WANG, Q. XU

《机械工程前沿(英文)》 2017年 第12卷 第2期   页码 193-202 doi: 10.1007/s11465-017-0448-8

摘要:

Large-aperture potassium dihydrogen phosphate (KDP) crystals are widely used in the laser path of inertial confinement fusion (ICF) systems. The most common method of manufacturing half-meter KDP crystals is ultra-precision fly cutting. When processing KDP crystals by ultra-precision fly cutting, the dynamic characteristics of the fly cutting machine and fluctuations in the fly cutting environment are translated into surface errors at different spatial frequency bands. These machining errors should be suppressed effectively to guarantee that KDP crystals meet the full-band machining accuracy specified in the evaluation index. In this study, the anisotropic machinability of KDP crystals and the causes of typical surface errors in ultra-precision fly cutting of the material are investigated. The structures of the fly cutting machine and existing processing parameters are optimized to improve the machined surface quality. The findings are theoretically and practically important in the development of high-energy laser systems in China.

关键词: ultra-precision fly cutting     large-aperture KDP crystals     spatial frequency     processing error    

Enhanced adsorption of phosphate by loading nanosized ferric oxyhydroxide on anion resin

Jing REN,Nan LI,Lin ZHAO,Nanqi REN

《环境科学与工程前沿(英文)》 2014年 第8卷 第4期   页码 531-538 doi: 10.1007/s11783-014-0629-1

摘要: Ferric oxyhydroxide loaded anion exchanger (FOAE) hybrid adsorbent was prepared by loading nanosized ferric oxyhydroxide (FO) on anion exchanger resin for the removal of phosphate from wastewater. TEM and XRD analysis confirmed the existence of FO on FOAE. After FO loading, the adsorption capacity of the hybrid adsorbent increased from 38.70 to 51.52 mg·g . Adsorption processes for both FOAE and anion resin were better fit to the pseudo first order model. Batch adsorption experiments revealed that higher temperature (313K), higher initial phosphate concentration (50 mg·L ) and lower solution pH (pH value of 2) would be more propitious to phosphate adsorption. Competition effect of coexisting anions on phosphate removal can be concluded as sulfate>nitrate>chloride. Freundlich isotherm model can describe the adsorption of phosphate on FOAE more accurately, which indicated the heterogeneous adsorption occurred on the inner-surface of FOAE.

关键词: phosphate removal     adsorption     nanosized ferric oxyhydroxide     anion exchanger    

Dynamic modulation performance of ferroelectric liquid crystal polarization rotators and Mueller matrix

Song ZHANG, Lelun WANG, Anze YI, Honggang GU, Xiuguo CHEN, Hao JIANG, Shiyuan LIU

《机械工程前沿(英文)》 2020年 第15卷 第2期   页码 256-264 doi: 10.1007/s11465-019-0573-7

摘要: A ferroelectric liquid crystal polarization rotator (FLCPR) has been widely used in polarization measurement due to its fast and stable modulation characteristics. The accurate characterization of the modulation performance of FLCPR directly affects the measurement accuracy of the instrument based on liquid crystal modulation. In this study, FLCPR is accurately characterized using a self-developed high-speed Stokes polarimeter. Strong linear and weak circular birefringence are observed during modulation processes, and all the optical parameters of FLCPR are dependent on driving voltage. A dual FLCPR-based Mueller matrix polarimeter is designed on the basis of the Stokes polarimeter. The designed polarimeter combines the advantages of the high modulation frequency of FLCPR and the ultrahigh temporal resolution of the fast polarization measurement system in the Stokes polarimeter. The optimal configuration of the designed polarizer is predicted in accordance with singular value decomposition. A simulated thickness measurement of a 24 nm standard SiO thin film is performed using the optimal configuration. Results show that the relative error in thickness measurement caused by using the unsatisfactory modulation characteristics of FLCPR reaches up to −4.34%. This finding demonstrates the importance of the accurate characterization of FLCPR in developing a Mueller matrix polarizer.

关键词: ferroelectric liquid crystal polarization rotator (FLCPR)     dual liquid crystal Mueller matrix polarizer     design and optimization    

Research progress on ultra-precision machining technologies for soft-brittle crystal materials

Hang GAO,Xu WANG,Dongming GUO,Yuchuan CHEN

《机械工程前沿(英文)》 2017年 第12卷 第1期   页码 77-88 doi: 10.1007/s11465-017-0411-8

摘要:

Soft-brittle crystal materials are widely used in many fields, especially optics and microelectronics. However, these materials are difficult to machine through traditional machining methods because of their brittle, soft, and anisotropic nature. In this article, the characteristics and machining difficulties of soft-brittle and crystals are presented. Moreover, the latest research progress of novel machining technologies and their applications for soft-brittle crystals are introduced by using some representative materials (e.g., potassium dihydrogen phosphate (KDP), cadmium zinc telluride (CZT)) as examples. This article reviews the research progress of soft-brittle crystals processing.

关键词: brittle     soft     functional crystal     ultra-precision machining    

A potentiometric cobalt-based phosphate sensor based on screen-printing technology

Lei ZHU,Xiaohong ZHOU,Hanchang SHI

《环境科学与工程前沿(英文)》 2014年 第8卷 第6期   页码 945-951 doi: 10.1007/s11783-013-0615-z

摘要: A potentiometric cobalt-based screen-printing sensor was fabricated by electroplating cobalt on the surface of a screen-printing electrode as the sensitive layer for the determination of dihydrogenphosphate ( ) in wastewater samples. The electrochemical performance of this sensor was fully examined to determine its detection calibration, detection limit, response time, selectivity, and interference with pH, various ions, and dissolved oxygen (DO). The cobalt-based phosphate sensor showed a phosphate-selective potential response in the range of 10 mol·L to 10 mol·L , yielding a detection limit of 3.16 × 10 mol?L and a slope of -37.51 mV?decade in an acidic solution (pH 4.0) of . DO and pH were found to interfere with sensor responses to phosphate. Ultimately, the performance of the sensor was validated for detecting wastewater samples from the Xiaojiahe Wastewater Treatment Plant against the standard spectrophotometric methods for analysis. The discrepancy between the two methods was generally ±5% (relative standard deviation). Aside from its high selectivity, sensitivity, and stability, which are comparable with conventional bulk Co-wire sensors, the proposed phosphate sensor presents many other advantages, such as low price, compactness, ease of use, and the possibility of integration with other analytical devices, such as flow injectors.

关键词: phosphate     cobalt     screen-printing technology     electroplate     wastewater    

料浆法磷铵生产工艺发展与五大磷肥工程改造

钟本和

《中国工程科学》 2004年 第6卷 第6期   页码 22-25

摘要:

针对引进磷酸浓缩工艺生产磷铵的技术不适应我国矿产资源具体情况的难题,开发了料浆法磷铵生产工艺技术,已在21个省区布点推广建设了87套装置,形成生产能力279×104 t/a的规模,占全国磷铵生产能力的60%。最近在贵州瓮福实施料浆法磷铵与引进的传统磷酸浓缩工艺联产的成功,为五大磷肥工程的改造提供了一条新的途径。

关键词: 磷肥     磷铵     料浆法磷铵    

Crystal-to-crystal transformation from the triclinic to the cubic crystal system by partial desolvation

Qianqian Guo, Irmgard Kalf, Ulli Englert

《化学科学与工程前沿(英文)》 2018年 第12卷 第3期   页码 433-439 doi: 10.1007/s11705-018-1743-6

摘要:

Diffusion reaction of the labile building block Mg(acacCN)2 (acacCN= 3-cyanoacetylacetonate) with silver salts leads to a series of solvated Mg/Ag bimetallic coordination polymers with composition [Mg(acacCN)3Ag]·solvent. Despite their common stoichiometry, the topology of these polymers depends on the solvent of crystallization. The two-dimensional coordination compound [Mg(acacCN)3Ag]·4CHCl3 in space group P1‾ is obtained as platelet-shaped crystals from a mixture of methanol and chloroform. When kept in the reaction mixture, these thin plates within one week convert to isometric tetrahedral crystals of the 3D network [Mg(acacCN)3Ag]·2CHCl3 in the cubic space group P213. The transformation reaction proceeds via dissolution and recrystallization. The co-crystallized solvent molecules play an important role for stabilizing the target structure: They subtend Cl···Cl contacts and interact via non-classical C–H···O hydrogen bonds with the coordination framework. In the new cubic coordination network, both Mg(II) and Ag(I) adopt octahedral coordination, with unprecedented face-sharing by bridging O atoms of three acetylacetonato moieties. Prolonged standing of [Mg(acacCN)3Ag]·2CHCl3 in the reaction medium leads to further degradation, under formation of [Ag(acacCN)].

关键词: ditopic ligand     substituted acetylacetone     desolvation     diffraction    

A space power system of free piston Stirling generator based on potassium heat pipe

Mingqiang LIN, Jian MOU, Chunyun CHI, Guotong HONG, Panhe GE, Gu HU

《能源前沿(英文)》 2020年 第14卷 第1期   页码 1-10 doi: 10.1007/s11708-019-0655-6

摘要: The power system of a free piston Stirling generator (FPSG) based on potassium heat pipes has been developed in this paper. Thanks to the advantages of long life, high reliability, and high overall thermal efficiency, the FPSG is a promising candidate for nuclear energy, especially in space exploration. In this paper, the recent progress of FPSG based on nuclear reactor for space use was briefly reviewed. A novel FPSG weighted only 4.2 kg was designed, and one dimensional thermodynamic modeling of the FPSG using Sage software was performed to estimate its performance. The experiment results indicated that this FPSG could provide 142.4 W at a thermal-to-electric efficiency of nearly 17.4%. Besides, the power system integrated with four FPSGs and potassium heat pipes was performed and the single machine failure test was conducted. The results show that this system could provide an electrical power of 300 W at an overall thermal efficiency of 7.3%. Thus, it is concluded that this power system is feasible and will have a great prospect for future applications.

关键词: free piston Stirling generator (FPSG)     potassium heat pipe     power system     energy conversion    

Effect of hierarchical ZSM-5 zeolite crystal size on diffusion and catalytic performance of n-heptane

Shuman Xu, Xiaoxiao Zhang, Dangguo Cheng, Fengqiu Chen, Xiaohong Ren

《化学科学与工程前沿(英文)》 2018年 第12卷 第4期   页码 780-789 doi: 10.1007/s11705-018-1733-8

摘要: Hierarchical ZSM-5 zeolite aggregates with different sizes of nanocrystals were synthesized using different amounts of the mesoporogen 3-aminopropyltriethoxysilane. The effect of the crystal size on the catalytic cracking of -heptane was investigated and the Thiele modulus and effectiveness factor were used to determine the reaction rate-limiting step. The crystal size affected the textual properties of the catalysts but not the acidic properties of the catalysts. The reaction rate was first order with respect to the -heptane concentration. Cracking over hierarchical zeolites with nanocrystal sizes larger than about 50 nm took place under transition-limiting conditions, whereas the reaction over hierarchical zeolites with nanocrystal sizes of 15 or 30 nm proceeded under reaction control conditions. Hierarchical ZSM-5 zeolite aggregates with smaller nanocrystals had better selectivity for light olefins which can be ascribed to the shorter diffusion path lengths and lower diffusion resistance in these catalysts. Furthermore, these catalysts had lower coking levels which can be attributed to the substantial number of mesopores which prevent the formation of coke precursors.

关键词: hierarchical ZSM-5     crystal size     catalytic cracking     Thiele modulus     effectiveness factor    

Effect of adding a smart potassium ion-responsive copolymer into polysulfone support membrane on the

Meibo He, Zhuang Liu, Tong Li, Chen Chen, Baicang Liu, John C. Crittenden

《化学科学与工程前沿(英文)》 2019年 第13卷 第2期   页码 400-414 doi: 10.1007/s11705-018-1757-0

摘要: Thin-film composite (TFC) nanofiltration (NF) membranes were fabricated via the interfacial polymerization of piperazine (PIP) and 1,3,5-benzenetricarbonyl trichloride on polysulfone (PSf) support membranes blended with K -responsive poly( -isopropylacryamide-co-acryloylamidobenzo-15-crown-5) (P(NIPAM-co-AAB C )). Membranes were characterized by attenuated total reflection Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, atomic force microscope, scanning electron microscope, contact angle, and filtration tests. The results showed that: (1) Under K -free conditions, the blended P(NIPAM-co-AAB C )/PSf supports had porous and hydrophilic surfaces, thereby producing NF membranes with smooth surfaces and low MgSO rejections; (2) With K in the PIP solution, the surface roughness and water permeability of the resultant NF membrane were increased due to the K -induced transition of low-content P(NIPAM-co-AAB C ) from hydrophilic to hydrophobic; (3) After a curing treatment at 95 °C, the improved NF membrane achieved an even higher pure water permeability of 10.97 L·m ·h ·bar under 200 psi. Overall, this study provides a novel method to improve the performance of NF membranes and helps understand the influence of supports on TFC membranes.

关键词: nanofiltration     interfacial polymerization     support membrane     potassium ion-responsive     thin-film composite    

Thermogravimetric coupled with Fourier transform infrared analysis study on thermal treatment of monopotassium phosphate

Yuheng FENG, Xuguang JIANG, Yong CHI, Xiaodong LI, Hongmei ZHU

《环境科学与工程前沿(英文)》 2011年 第5卷 第2期   页码 186-192 doi: 10.1007/s11783-011-0322-6

摘要: In China, safe disposal of hazardous waste is more and more a necessity, urged by rapid economic development. The pyrolysis and combustion characteristics of a residue from producing monopotassium phosphate (monopotassium phosphate residue), considered as a hazardous waste, were studied using a thermogravimetric, coupled with Fourier transform infrared analyzer (TG-FTIR). Both pyrolysis and combustion runs can be subdivided into three stages: drying, thermal decomposition, and final devolatilization. The average weight loss rate during fast thermal decomposition stage in pyrolysis is higher than combustion. Acetic acid, methane, pentane, (acetyl) cyclopropane, 2,4,6-trichlorophenol, CO, and CO were distinguished in the pyrolysis process, while CO was the dominant combustion product.

关键词: hazardous waste     combustion     pyrolysis     thermogravimetric coupled with Fourier transform infrared analysis (TG-FTIR)     monopotassium phosphate residue    

标题 作者 时间 类型 操作

Experimental study on high-efficiency polishing for potassium dihydrogen phosphate (KDP) crystal by using

Ziyuan LIU, Hang GAO, Dongming GUO

期刊论文

Influences of additives on the crystal habit of potassium chloride

Xiaofu GUO, Junsheng YUAN, Zhiyong JI, Min SU,

期刊论文

Solvates and polymorphs of clindamycin phosphate: Structural, thermal stability and moisture stability

Junbo Gong, Dejiang Zhang, Yuanyuan Ran, Keke Zhang, Shichao Du

期刊论文

Effect of potassium carbonate on catalytic synthesis of calcium carbide at moderate temperature

Dejun SHI, Ke QIAO, Zifeng YAN

期刊论文

control and crack-free surface fabrication techniques for ultra-precision fly cutting of large-aperture KDP

F. H. ZHANG, S. F. WANG, C. H. AN, J. WANG, Q. XU

期刊论文

Enhanced adsorption of phosphate by loading nanosized ferric oxyhydroxide on anion resin

Jing REN,Nan LI,Lin ZHAO,Nanqi REN

期刊论文

Dynamic modulation performance of ferroelectric liquid crystal polarization rotators and Mueller matrix

Song ZHANG, Lelun WANG, Anze YI, Honggang GU, Xiuguo CHEN, Hao JIANG, Shiyuan LIU

期刊论文

Research progress on ultra-precision machining technologies for soft-brittle crystal materials

Hang GAO,Xu WANG,Dongming GUO,Yuchuan CHEN

期刊论文

A potentiometric cobalt-based phosphate sensor based on screen-printing technology

Lei ZHU,Xiaohong ZHOU,Hanchang SHI

期刊论文

料浆法磷铵生产工艺发展与五大磷肥工程改造

钟本和

期刊论文

Crystal-to-crystal transformation from the triclinic to the cubic crystal system by partial desolvation

Qianqian Guo, Irmgard Kalf, Ulli Englert

期刊论文

A space power system of free piston Stirling generator based on potassium heat pipe

Mingqiang LIN, Jian MOU, Chunyun CHI, Guotong HONG, Panhe GE, Gu HU

期刊论文

Effect of hierarchical ZSM-5 zeolite crystal size on diffusion and catalytic performance of n-heptane

Shuman Xu, Xiaoxiao Zhang, Dangguo Cheng, Fengqiu Chen, Xiaohong Ren

期刊论文

Effect of adding a smart potassium ion-responsive copolymer into polysulfone support membrane on the

Meibo He, Zhuang Liu, Tong Li, Chen Chen, Baicang Liu, John C. Crittenden

期刊论文

Thermogravimetric coupled with Fourier transform infrared analysis study on thermal treatment of monopotassium phosphate

Yuheng FENG, Xuguang JIANG, Yong CHI, Xiaodong LI, Hongmei ZHU

期刊论文