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An oxidizing roasting process of carbon ferrochrome to prepare sodium chromate in the presence of sodium carbonate and air was investigated. The effects of reaction temperature, reaction time, mole ratio of sodium carbonate to carbon ferrochrome were studied, and thermodynamics and kinetics of the reaction were also discussed. It was observed that there was a sudden increase in reaction rate when the temperature rose to a certain value, and the sample with a smaller grain size could start the sudden increase at a lower temperature. The chromium recovery rate increased with the increase of mole ratio of sodium carbonate to carbon ferrochrome, and it reached up to 99.34% when mole ratio of sodium carbonate to carbon ferrochrome increased to 1.2:1. The chromium residue yielded from this method was only about 1/3 of the product. Moreover, the content of Fe in the residue was as high as 60.41%. Therefore, it can be easily recovered to produce sponge iron, realizing complete detoxication and zero-emission of chromium residue.

The oxidizing roasting process of carbon ferrochrome to prepare potassium chromate in the presence of potassium carbonate and air was investigated. The effects of reaction temperature, reaction time, mole ratio of potassium carbonate to carbon ferrochrome were studied, and thermodynamics and kinetics were also discussed. It was observed that the reaction temperature and reaction time had a significant influence on the roasting reaction of carbon ferrochrome. The reaction mechanism changed greatly as the temperature varied. A two-stage roasting process was favorable for the roasting reaction, and a chromium recovery rate of 97.06% was obtained through this two-stage roasting method. The chromium residue yielded from this method was only 1/3 of the product. Moreover, the component of Fe in the residue was as high as 55.04%. Therefore, it can be easily recovered to produce sponge iron, realizing complete detoxication and zero-emission of chromium residue.

A novel synthesis of LiFePO4/C from Fe2O3 with no extra carbon or carbon-containing reductant was introduced: Fe2O3 (+NH4H2PO4)→Fe2P2O7(+Li2CO3+glucose)→LiFePO4/C. X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were utilized to characterize relevant products obtained in the synthetic procedure. The reaction of Fe2P2O7 and Li2CO3 was investigated by thermo-gravimetric and differential thermal analysis (TGA-DTA). Fe2O3 is completely reduced to Fe2P2O7 by NH4H2PO4 at 700 °C and Fe2P2O7 fully reacts with Li2CO3 to form LiFePO4 in the temperature range of 663.4–890 °C. The primary particles of LiFePO4/C samples prepared at 670, 700 and 750 °C respectively exhibit uniform morphology and narrow size distribution, 0.5–3 μm for those obtained at 670 and 700 °C and 0.5–5 μm for those obtained at 750 °C. LiFePO4/C (carbon content of 5.49%, mass fraction) made at 670 °C shows an appreciable average capacity of 153.2 mA·h/g at 0.1C in the first 50 cycles.

A facile and practical route was introduced to prepare LiFePO4/C cathode material with nano-sized primary particles and excellent electrochemical performance. LiH2PO4 was synthesized by using H3PO4 and LiOH as raw materials. Then, as-prepared LiH2PO4, reduced iron powder and a-D-glucose were ball-milled, dried and sintered to prepare LiFePO4/C. X-ray diffractometry was used to characterize LiH2PO4, ball-milled product and LiFePO4/C. Differential scanning calorimeter-thermo gravimetric analysis was applied to investigate possible reactions in sintering and find suitable temperature for LiFePO4 formation. Scanning electron microscopy was employed for the morphology of LiFePO4/C. As-prepared LiH2PO4 is characterized to be in P21cn(33) space group, which reacts with reduced iron powder to form Li3PO4, Fe3(PO4)2 and H2 in ball-milling and sintering. The appropriate temperature for LiFePO4/C synthesis is 541.3-976.7 °C. LiFePO4/C prepared at 700 °C presents nano-sized primary particles forming aggregates. Charge-discharge examination indicates that as-prepared LiFePO4/C displays appreciable discharge capacities of 145 and 131 mA·h·g−1 at 0.1 and 1 C respectively and excellent discharge capacity retention.

As an improvement on the conventional two-layer electrode (active material layer|current collector), a novel sandwich-like three-layer electrode (conductive layer|active material layer|current collector) for cathode material LiFePO 4 /C was introduced in order to improve its electrochemical performance. LiFePO 4 /C in the three-layer electrode exhibited superior rate capability in comparison with that in the two-layer electrode in accordance with charge-discharge examination. Cyclic voltammetry and electrochemical impedance spectroscopy indicated that Fe 3+ /Fe 2+ redox couple for LiFePO 4 in the three-layer electrode displayed faster kinetics, better reversibility and much lower charge transfer resistance than that in the two-layer electrode in electrochemical process. For three-layer electrode, the holes in the surface of active material layer were filled by smaller acetylene black grains, which formed electrical connections and provided more pathways to electron transport to/from LiFePO 4 /C particles exposed to the bulk electrolyte.

W-doped Li4Ti5O12 in the form of Li4Ti4.95W0.05O12 was firstly synthesized via solid state reaction. X-ray diffraction (XRD) and scanning electron microscope (SEM) were employed to characterize the structure and morphology of Li4Ti4.95W0.05O12. W-doping does not change the phase composition and particle morphology, while remarkably improves its cycling stability at high charge/discharge rate. Li4Ti4.95W0.05O12 exhibits an excellent rate capability with a reversible capacity of 131.2 mA·h/g at 10C and even 118.6 mA·h/g at 20C. The substitution of W for Ti site can enhance the electronic conductivity of Li4Ti5O12 via the generation of mixing Ti4+/Ti3+, which indicates that Li4Ti4.95W0.05O12 is promising as a high rate anode for the lithium-ion batteries.

Co, Mn and Mg co-doped lithium nickel oxides of the nominal composition LiNi0.9Co0.1−x[Mn1/2Mg1/2]xO2 (x = 0.00, 0.02, 0.04, 0.06) are synthesized by a co-precipitation technique and solid state route. XPS results reveal that the oxidation states of Ni, Co, Mn and Mg are +3, +3, +4 and +2, respectively. An ordered α-NaFeO2 rock salt structure with R − 3 ¯ m symmetry has been confirmed by XRD. The cation mixing of Li/Ni and occupation of Mg ions have been analyzed by Rieveld refinement. Mg ions distribute between 3b and 3a sites in the crystal. Meanwhile a substantial reduction of cation mixing of Li–Ni has been confirmed by Mn–Mg substitution. Better cycling performance is observed in the compound with high Mn–Mg content compared with LiNi0.9Co0.1O2. Mn–Mg substitution for Co has been shown to suppress the increase of the cell impedance during cycles effectively.

以Na 2 SiO 3 ·9H 2 O和FeCl 2 ·4H 2 O为原料, 采用低热固相反应获得了分散均匀的β-FeOOH/SiO 2 前驱体; 再以Li 2 CO 3 为锂源、聚乙烯醇和超导电炭黑为复合碳源, 通过微波辅助固相法合成了Li 2 FeSiO 4 /C材料. 通过X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)和恒电流充放电测试等方法对材料的结构、微观形貌及电化学性能进行表征. 650℃下微波处理12 min可获得结晶好、晶粒细小均匀的Li 2 FeSiO 4 /C材料; 在选用的微波合成体系下, 超导碳和聚乙烯醇热分解的无定形碳不仅利于合成反应的顺利进行, 而且提高了Li 2 FeSiO 4 的整体导电性能. 制备的复合正极材料在60 ℃下0.05 C 倍率首次放电容量为129.6 mAh/g, 0.5 C 倍率下为107.5 mAh/g, 0.5 C 下15次循环后保持为104.8 mAh/g, 具有较好的放电比容量和良好的循环稳定性能. 结果表明, 微波辅助固相合成工艺是制备Li 2 FeSiO 4 /C复合材料的一种很有前景的方法.

LiFePO4/C composite was prepared by two-step synthesis route, with LiH2PO4 and FeC2O4· 2H2O as starting materials. In the process, the carbon sources polyvinyl alcohol (PVA) and glucose were added in a stepwise fashion. The well-crystallized LiFePO4/C composite with homogeneous small particles was obtained after reacting at 700 °C for 4 h. This composite had a discharge specific capacity of 157.3 mAh·g-1 at 0.1C rate and 138.4 mAh·g-1 at 1C rate. On the basis of carbon coating modification, Nb-ion-doped LiFe1-xNbxPO4/C (x=0.005, 0.01, 0.015, 0.02) composites were prepared. The optimized LiFe0.99Nb0.01PO4/C cathode displayed a discharge specific capacity 160.5 mAh·g-1 at 0.1C discharge rate, 136.0 mAh·g-1 at 5C and maintained 134.8 mAh·g-1 after 50 cycles, showing good rate properties and cycling stability. Cyclic voltammetry (CV) measurements indicated that aliovalent dopant substituting on the Fe sites can reduce the resistance of Li ion diffusion in the electrode process, increase phase transformation kinetics during cycling, and enhance the reversibility of LiFePO4 electrodes.

A Co Mn Mg co-substituted LiNi 0.9 Co 0.05 [Mn 1/2 Mg 1/2 ] 0.05 O 2 solid solution was synthesized and characterized by XRD, XPS, SEM and its electrochemical electrochemical performance was investigated. Potato-like (~ 15 μm) single phase LiNi 0.9 Co 0.05 [Mn 1/2 Mg 1/2 ] 0.05 O 2 compound was obtained and its crystal structure was analyzed by Rietveld refinements. XPS results showed that Ni, Co, Mn and Mg at the surface of LiNi 0.9 Co 0.05 [Mn 1/2 Mg 1/2 ] 0.05 O 2 powder exist at + 4, + 3, + 3 and + 2 oxidation states respectively. And Ni in the bulk was also determined to occur as electrochemical-active Ni 3 + ion, which is beneficial for high capacity electrode. The synthesized LiNi 0.9 Co 0.05 [Mn 1/2 Mg 1/2 ] 0.05 O 2 can deliver a high initial discharge capacity of 191.5 mAhg − 1 at 0.2C rate and more than 93% of the initial specific discharge capacity was retained after 50 cycles.

A low-temperature approach for efficient preparation of LiFePO4 was developed. The rod-shaped [Fe3(PO4)2·8H2O + Li3PO4] precursor was prepared, using a mechanochemical liquid-phase activation technique, from LiH2PO4 and reduction iron powder. Pure LiFePO4 was then synthesized in boiling tetra(ethylene glycol) (TEG) by polyol processing with the as-prepared precursor. In order to improve the electrical conductivity, carbon coating of the pure LiFePO4 was carried out, using poly(vinyl alcohol) (PVA) as the carbon source. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), galvanostatic charge-discharge test and electrochemical impedance spectroscopy (EIS). The results show that well-crystallized LiFePO4 was successfully synthesized by polyol processing at low temperature. Carbon coating significantly improves the conductive properties of LiFePO4 and reduces charge-transfer impedance. The obtained LiFePO4/C composite delivers specific discharge capacities of 139.8 and 129.5 mAh·g-1 at 1C and 2C rates, respectively, displaying good cycling performance and rate capability.

The electrochemical performance of Ta-doped Li4Ti5O12 in the form of Li4Ti4.95Ta0.05O12 was characterized. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed to characterize the structure and morphology of Li4Ti4.95Ta0.05O12. Ta-doping does not change the phase composition and particle morphology, while improves remarkably its cycling stability at high charge/discharge rate. Li4Ti4.95Ta0.05O12 exhibits an excellent rate capability with a reversible capacity of 116.1 mA·h/g at 10C and even 91.0 mA·h/g at 30C. The substitution of Ta for Ti site can enhance the electronic conductivity of Li4Ti5O12 via the generation of mixing Ti4+/Ti3+, which indicates that Li4Ti4.95Ta0.05O12 is a promising candidate material for anodes in lithium-ion battery application.

Spherical Ni 0.8 Co 0.15 Al 0.05 OOH precursor, prepared by a co-oxidation-controlled crystallization method, was used to synthesize LiNi 0.8 Co 0.15 Al 0.05 O 2 . The obtained LiNi 0.8 Co 0.15 Al 0.05 O 2 materials showed excellent electrochemical performance, with an initial discharge capacity of 193.5 mAh/g and capacity retention of 95.1% after 50 cycles when cycled at 0.2 C rate between 2.8 and 4.3 V.

Platinum nanoparticles supported on carbons (Pt/C, 60%, mass fraction) electrocatalysts for direct methanol fuel cell (DMFC) were prepared by citrate-stabilized method with different reductants and carbon supports. The catalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and cyclic voltammetry (CV). It is found that the size of Pt nanoparticles on carbon is controllable by citrate addition and reductant optimization, and the form of carbon support has a great influence on electrocatalytic activity of catalysts. The citrate-stabilized Pt nanoparticles supported on BP2000 carbon, which was reduced by formaldehyde, exhibit the best performance with about 2 nm in diameter and 66.46 m^2/g(Pt) in electrocatalytic active surface (EAS) area. Test on single DMFC with 60% (mass fraction) Pt/BP2000 as cathode electrocatalyst showed maximum power density at 78.8 mW/cm^2.

LiMn2O4 spinel cathode materials were modified with 2 wt.% Li–M–PO4 (M = Co, Ni, Mn) by polyol synthesis method. The phosphate surface-modified LiMn2O4 cathode materials were physically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The charge–discharge test showed that the cycling and rate capacities of LiMn2O4 cathode materials were significantly enhanced by stabilizing the electrode surface with phosphate.

The effect of Cr-sources on the performance of Li 1.05 Cr 0.04 Mn 1.96 O 4 prepared by slurry spray drying method was studied by adopting three different chromic compounds, Cr 2 O 3 , Cr 2 (SO 4 ) 3 and Cr(CH 3 COO) 3 , respectively. The prepared powder materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), laser particle size analyzer and Brunauer–Emmett–Teller (BET) specific surface area test. Electrochemical performances of these cathode materials were investigated by electrochemical impedance spectroscopy (EIS) and charge–discharge tests with Li/LiCr x Mn 2− x O 4 coin-type batteries. The results indicate that porous spherical particles with average particle size of about 24 μm can be obtained by slurry spray drying process. Using Cr(CH 3 COO) 3 as Cr-source resulted in the better mixing properties, which can make the as-prepared CA-Li 1.05 Cr 0.04 Mn 1.96 O 4 having smaller lattice parameter, smaller grain size and better structure stability, and consequently the obtained sample showed low charge transfer impedance and electrochemical polarization, and exhibited good electrochemical performance at elevated temperature.

Micro-spherical particle of MnCO 3 has been successfully synthesized in CTAB–C 8 H 18 –C 4 H 9 OH–H 2 O micro-emulsion system. Mn 2 O 3 decomposed from the MnCO 3 is mixed with Li 2 CO 3 and sintered at 800 °C for 12 h, and the pure spinel LiMn 2 O 4 in sub-micrometer size is obtained. The LiMn 2 O 4 has initial discharge specific capacity of 124 mAh g −1 at discharge current of 120 mA g −1 between 3 and 4.2 V, and retains 118 mAh g −1 after 110 cycles. High-rate capability test shows that even at a current density of 16 C, capacity about 103 mAh g −1 is delivered, whose power is 57 times of that at 0.2 C. The capacity loss rate at 55 °C is 0.27% per cycle.

A novel synthetic method of microwave processing to prepare Li 2 FeSiO 4 cathode materials is adopted. The Li 2 FeSiO 4 cathode material is prepared by mechanical ball-milling and subsequent microwave processing. Olivin-type Li 2 FeSiO 4 sample with uniform and fine particle sizes is successfully and fast synthesized by microwave heating at 700 °C in 12 min. And the obtained Li 2 FeSiO 4 materials show better electrochemical performance and microstructure than those of Li 2 FeSiO 4 sample by the conventional solid-state reaction.

LiNi 0.8 Co 0.2 O 2 particles were modified by Co 3 (PO 4 ) 2 coating. The effects of the Co 3 (PO 4 ) 2 coating on the structure and electrochemical properties of the LiNi 0.8 Co 0.2 O 2 cathode material were investigated. The Co 3 (PO 4 ) 2 coating forms a thin layer on the surface of the LiNi 0.8 Co 0.2 O 2 material and a solid solution by interacting with the LiNi 0.8 Co 0.2 O 2 core material during calcination at 700°C for 4 h. Charge-discharge experiment results show that the Co 3 (PO 4 ) 2 coating improves the cycling stability of the LiNi 0.8 Co 0.2 O 2 cathode material. The capacity retention of the pristine LiNi 0.8 Co 0.2 O 2 cathode after 50 cycles is 83.6%, whereas it is 91.7% in the case of the LiNi 0.8 Co 0.2 O 2 cathode coated with 1 wt.% Co 3 (PO 4 ) 2 . Storage tests of the 4.35 V charged electrode at 60°C after a month show that the Co 3 (PO 4 ) 2 -coated sample exhibits good storage properties compared with the pristine sample.

This paper studies non-convex programming problems. It is known that, in statistical inference, many constrained estimation problems may be expressed as convex programming problems. However, in many practical problems, the objective functions are not convex. In this paper, we give a definition of a semi-convex objective function and discuss the corresponding non-convex programming problems. A two-step iterative algorithm called the alternating iterative method is proposed for finding solutions for such problems. The method is illustrated by three examples in constrained estimation problems given in Sasabuchi et al. (Biometrika, 72, 465–472 (1983)), Shi N. Z. (J. Multivariate Anal., 50, 282–293 (1994)) and El Barmi H. and Dykstra R. (Ann. Statist., 26, 1878–1893 (1998)).

A compound ”vacuum firing and water quenching” technique was presented in the synthesis of LiFePO4 cathode powder. The sample was prepared by heating the pre-decomposed precursor mixtures sealed in vacuum quartz-tube, followed by water quenching at the sintering temperature. The results indicate that using the ”fast quenching” treatment can succeed in controlling overgrowth of the grain size of final product and improving its utilization ratio of active material. The sample synthesized by this technique has the high reversible discharge specific capacity and good cyclic electrochemical performance.

Spherical Li(Ni(subscript 1/3)Mn(subscript 1/3)Co(subscript 1/3))O2 was prepared via the homogenous precursors produced by solution spray-drying method. The precursors were sintered at different temperatures between 600 and 1000℃ for 10h. The impacts of different sintering temperatures on the structure and electrochemical performances of Li(Ni(subscript 1/3)Mn(subscript 1/3)Co(subscript 1/3))O2 were compared by means of X-ray diffractometry(XRD), scanning electron microscopy(SEM), and charge/discharge test as cathode materials for lithium ion batteries. The experimental results show that the spherical morphology of the spray-dried powers maintains during the subsequent heat treatment and the specific capacity increases with rising sintering temperature. When the sintering temperature rises up to 900℃, Li(Ni(subscript 1/3)Mn(subscript 1/3)Co(subscript 1/3))O2 attains a reversible capacity of 153 mA•h/g between 3.00 and 4.35V at 0.2C rate with excellent cyclability.

To improve the performance of LiFePO4, single phase Li(subscript 1-4x)Ti(subscript x)FePO4/C(x=0,0.005, 0.010, 0.015) cathodes were synthesized by solid-state method. A certain content of glucose was used as carbon precursor and content of carbon in every final product was about 3.5%. The samples were characterized by X-ray diffraction(XRD), scanning electron microscopy observations(SEM), charge/discharge test, carbon analysis and electrochemical impedance spectroscopy(EIS). The results indicate that the prepared samples have ordered olivine structure and doping of the low concentration Ti(superscript 4+) does not affect the structure of the samples. The electrochemical capabilities evaluated by charge-discharge test show that the sample with 1% Ti(superscript 4+) (molar fraction) has good electrochemical performance delivering about an initial specific capacity of 146.7mA•h/g at 0.3C rate. Electrochemical impedance spectroscopy measurement results show that the charge transfer resistance of the sample could be decreased greatly by doping an appropriate amount Ti(superscript 4+).

LiFePO 4 /C was synthesized by high temperature solid-state method with cheap Fe 2 O 3 , LiH 2 PO 4 and glucose as raw materials in absence of inert gas. The sample had ordered olivine-type structure other impurities characterized by the test of X-ray diffraction (XRD). The charge-discharge test showed the sample could demonstrate 120.5 mAh/g at 0.2C rate with good cyclic capability. The powder microelectrode cyclic voltammetry test indicated that the redox process of the sample had good reversibility.

To improve the performance, the surface of LiMn2O4 was coated with very fine MgO, Al2O3 and ZnO by sol-gel method, respectively. The structure and morphology of the coated materials were investigated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The charge and discharge performance of uncoated and surface modified LiMn2O4 spinel at 25°C and 55°C were tested, using a voltage window of 3.0–4.35 V and a current density of 0.1 C rate. There is a slight decrease in the initial discharge capacity relative to that of uncoated LiMn2O4, but the cycle ability of Li LiMn2O4 coated by metal-oxide has remarkably been improved. The EIS measurements of uncoated and Al2O3-coated LiMn2O4 were carried out by a model 273 A potentiostat/galvanistat controlled by a computer using M270 software, and using a frequency response analyzer (Zsimpwin) combined with a potentiostate (PAR 273). Consequently, the reason for the improved cycle properties is that the surface modification reduces the dissolution of Mn, which results from the suppression of the electrolyte decomposition, and suppresses the formation of passivation film that acts as an electronic insulating layer. In conclusion, the use of surface modification is an effective way to improve the electrochemical performance of LiMn2O4 cathode material for lithium batteries.

The goal of the Enhanced Versatile Disc (EVD) standard is to define an advanced high definition disc competing with Digital Versatile Disc (DVD). The EVD standard consists of the physical specification, the file system specification, and the specification for audio/video data and Enhanced(x) Audio Coding (ExAC) technology. EVD is an integrated system similar to DVD. Comprehensive comparisons of EVD and DVD are given in this paper. Their key differences include disc formats, file system structures, data structures, audio/video coding, and other issues. Among them, we emphasize on the logic structure of EVD data and its enhanced audio coding method ExAC. We can draw conclusions through these comparisons that EVD is more the advantageous.

LiMn2−xMxO4−yFy(x=0.05; y=0.05; M=Al, Co, Cr and Mg, separately), as the cathode material, was synthesized by the method of high temperature solid-state reaction in laboratory. The results of charge-discharge test show that the properties of LiMn1.95M0.05O3.95F0.05(M= Al, Mg) are obviously superior to those of LiMn2O4. Through the condition experiments on sintering temperature, it is found that the materials present the integrate crystal structure and favorable cycle performance at 800 °C. The research on the effects of different Mg2+ sources on the properties of LiMn2−xMgxO4−yFy shows that, with Mg(OH)2 and LiF as the reagents respectively offering Mg2+ and F−, LiMn1.95Mg0.05O3.95F0.05 synthesized has integrate crystal structure and its capacity hardly fades. The results of cyclic voltammetry indicate that the shape of two couples of redox peaks of the material synthesized by co-doping anti-electricity ions is more integrate and symmetrical than that of pure spinel LiMn2O4, which reveals that the co-doping material possesses preferable electrochemical reversibility.

The cathode material LiCo1−xLaxO2(x=0, 0.01, 0.02, 0.05) for Li-ion battery was prepared in solid phase. Effects of La dopant on the structure were analyzed by X-ray diffraction, and the morphology of the samples was observed by scanning electron microscopy. The results show that the structure of LiCoO2 becomes more and more non-perfect with the increasing content of La and some impurity peaks appear in the XRD pattern when the La content reaches 0.05. Meanwhile, a high synthesis temperature is advantageous to the intact and unitary compound. The initial discharge capacity of doped material containing La (x=0.01) synthesized at 900 °C reaches 160 mAh/g by charge-discharge test, which prior to that of non-doped material synthesized under the same condition. However, the increasing La content deteriorates the cycling performance. Therefore, the appropriate content of La is 0.01 and the optimum synthesis temperature is 900°C.

The spinel LiMn2O4 used as cathode materials for lithium-ion batteries was synthesized by mechano-chemistry fluid activation process, and modified by doping rare-earth Sm. Thesting of X-ray diffraction, cyclic voltammograms, charge-discharge and SEM was carried out for LiMn2O4 cathode materials and the modified materials. The results show that the cathode materials doped rare earth LixMn2−ySmzO4 (0.95⩽x⩽1.2, 0⩽y⩽0.3, 0⩽z⩽0.2) exhibit standard spinel structure, high reversibility of electrochemistry and excellent properties of charge-discharge. In EC: DMC(1 : 1)+1 mol/L LiPF6 electrolyte with discharge capacity more than 130 mA · h/g, and its capacity is deteriorated less than 15% after 300 cycles at room temperature and less than 20% after 200 cycles at 55°C. At the same time, Crystal Field Theory was applied to explain the function and mechanism of doped rare earth element.

Microwave synthesis method was applied to the fast preparation of LiCoO2. The structure of the synthesized oxides was analyzed by using X-ray diffraction. Only single-phase LiCoO2 was obtained. Electrochemical behaviors of LiCoO2 were investigated by charge-discharge cycling properties in the voltage range of 3.00 – 4.35 V (vs Li). The results show that the prepared LiCoO2 powders calcinated at 900 °C for 120 min exhibit an initial charge and discharge capacity of 168 and 162 mA · h · g−1 at 0.1C current rate, respectively, as compared to 159 and 154 mA · h · g−1 of LiCoO2 synthesized by conventional means. In addition, more than 95% of the capacity is retained even after 10 cycles. But with the increase of calcinating time, its electrochemical properties deteriorate. Compared with the conventional method, the microwave heating method is simple, fast, and with high energy efficiency.

Offwhite pure Fe 2 P 2 O 7 was synthesized through solid phase reaction using Fe 2 O 3 and NH 4 H 2 PO 4 in argon atmosphere. The reaction products of Fe 2 O 3 and NH 4 H 2 PO 4 at a series of temperatures from 400 to 900 °C were characterized by XRD. Comparison and analysis of XRD patterns of resultant products indicated well-crystallized Fe 2 P 2 O 7 could be obtained over 630 °C and Fe 2 P 2 O 7 prepared at 700 °C was triclinic in cell type. Comparison of the cell parameters proved that the as-prepared Fe 2 P 2 O 7 belonged to β-Fe 2 P 2 O 7 in crystal phase and SEM showed its size distribution was 0.5–2 μm.

The coating of Ni-W-P was deposited as base-layer, and then the composite coating of Ni-Ti(particles)-Re(rare earth) was deposited subsequently on the surface of diamond using electroless plating by adding 2 – 3 µm Ti particles and trace rare earth salt to bath solution. Ti particles deposited on the surface of diamond were found by SEM and formation of TiC was verified by X-ray diffraction analysis after heat treatment of the coatings in vacuum at 900 °C. The binding strength between the coated diamond and the metal matrix was improved effectively in the diamond composite based on metal cement.

Offwhite pure Fe 2 P 2 O 7 was synthesized through solid phase reaction using Fe 2 O 3 and NH 4 H 2 PO 4 in argon atmosphere. The reaction products of Fe 2 O 3 and NH 4 H 2 PO 4 at a series of temperatures from 400 to 900 °C were characterized by XRD. Comparison and analysis of XRD patterns of resultant products indicated well-crystallized Fe 2 P 2 O 7 could be obtained over 630 °C and Fe 2 P 2 O 7 prepared at 700 °C was triclinic in cell type. Comparison of the cell parameters proved that the as-prepared Fe 2 P 2 O 7 belonged to β-Fe 2 P 2 O 7 in crystal phase and SEM showed its size distribution was 0.5–2 μm.

This paper describes a new technique to determine the attitude of microsatellite using Global Positioning System (GPS) signals. A new method, LAMDA method, is applied to deal with the double difference integer ambiguity. At the same time it is combined with Kalman Filtering to solve the real-time ambiguity and the baseline vector. The direct method for attitude determination with three antennas is described in details. The test results are also presented to show how accurate results this new technique can achieve.

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