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Objective To investigate the feasibility and efficacy of sight-guided percutaneous unilateral translaminar facet screw fixation (TLFSF) with interbody fusion for treatment of lower lumbar vertebra diseases. Methods Twenty-nine adult patients with lower lumbar disease underwent sight-guided percutaneous unilateral TLFSF combined with microsurgical spinal decompression, discectomy, and interbody fusion from June 2007 to June 2008. All 29 patients had low back pain caused by lumbar disc degeneration (20 cases), in situ recurrent lumbar disc herniation (2), primary diskitis (1), lumbar disc herniation with spinal stenosis (3), and first-degree lumbar degenerative spondylolisthesis (3). Twenty-three cases had lesions at L4,5; three at L5S1, one at L3,4, L4,5, and two at L4,5, L5S1. Results No patient experienced significant postoperative complications. The mean incision length was 4.48 ± 0.55 cm; operative time 1.34 ± 0.22 h; intraoperative blood loss 280 ± 175 mL; and postoperative drainage volume 165 ± 85 mL. Screw position results: type I, 21 cases (23 segments); type II, 7 cases (8 segments); and type III, 1 case (1 segment). Twenty-eight patients were followed up for 24–60 months (average, 47.5 months). Interbody fusion rate was 93.5%). Postoperative intervertebral height recovered significantly; however, loss of intervertebral height oc urred during follow-up. Conclusion Sight-guided percutaneous unilateral TLFSF with interbody fusion for treatment of lower lumbar disease is simple and minimally invasive, with good screw accuracy and security, high fusion rate, and good efficacy. However, specific surgical indications must be strictly followed.

The photocatalytic removal of phenol was studied using palygorskite-SnO 2 –TiO 2 composites (abbreviated as Paly-SnO 2 –TiO 2 ) under ultraviolet radiation. The photocatalysts were prepared by attachment of SnO 2 –TiO 2 oxides onto the surface of the palygorskite by in situ sol–gel technique. The products were characterized by XRD, TEM and BET measurements. SnO 2 –TiO 2 nanoparticles, with an average diameter of about 10 nm, covered the surface of the palygorskite fibers without obvious aggregation. Compared with palygorskite-titania (Paly-TiO 2 ), palygorskite-tin dioxide (Paly-SnO 2 ), and Degussa P25, Paly-SnO 2 –TiO 2 and SnO 2 –TiO 2 exhibited much higher photocatalytic activity. The photodecomposition of phenol was as high as 99.8% within 1.5 h. The apparent rate constants ( k app ) for Paly-SnO 2 –TiO 2, TiO 2 , and P25 were measured. Paly-SnO 2 –TiO 2 showed the highest rate constant (0.03435 min −1 ). The chemical oxygen demand (COD) of the phenol solution was reduced from 220.2 mg/L to 0.21 mg/L, indicating the almost complete decomposition of phenol. Reusability of the photocatalyst was proved.

Digital superconductor electronics has been experiencing rapid maturation with the emergence of smaller-scale, lower-cost communications applications which became the major technology drivers. These applications are primarily in the area of wireless communications, radar, and surveillance as well as in imaging and sensor systems. In these areas, the fundamental advantages of superconductivity translate into system benefits through novel Digital-RF architectures with direct digitization of wide band, high frequency radio frequency (RF) signals. At the same time the availability of relatively small 4K cryocoolers has lowered the foremost market barrier for cryogenically-cooled digital electronic systems. Recently, we have achieved a major breakthrough in the development, demonstration, and successful delivery of the cryocooled superconductor digital-RF receivers directly digitizing signals in a broad range from kilohertz to gigahertz. These essentially hybrid-technology systems combine a variety of superconductor and semiconductor technologies packaged with two-stage commercial cryocoolers: cryogenic Nb mixed-signal and digital circuits based on Rapid Single Flux Quantum (RSFQ) technology, room-temperature amplifiers, FPGA processing and control circuitry. The demonstrated cryocooled digital-RF systems are the world's first and fastest directly digitizing receivers operating with live satellite signals in X-band and performing signal acquisition in HF to L-band at ∼30GHz clock frequencies.

The solid-liquid phase equilibrium for the quaternary system Na2SO4-NaCl-H2O2-H2O was studied at 283.15 K by Schreinemaker’s wet residues method. The solubility data for the quaternary system were measured, and the phase diagram was constructed. When the concentration of hydrogen peroxide employed in the experiments was below 50 mass%, four solid phases were present in the quaternary system, which corresponded to NaCl, Na2SO4·10H2O, Na2SO4·0.5H2O2·H2O, and 4Na2SO4·2H2O2·NaCl. The phase diagram of the quaternary system included two invariant points and four crystalline zones. The crystalline region of 4Na2SO4·2H2O2·NaCl was larger than those of NaCl, Na2SO4·10H2O, or Na2SO4·0.5H2O2·H2O.

In this investigation, the mutual solubilities for the ternary Mg(CH3COO)2-CH3COOH-H2O system were determined at 298.1 and 333.1 K. Two partial isothermal phase diagrams for this ternary system were constructed on the basis of the measured solubilities, one at 298.1 K and the other at 333.1 K. At 298.1 K, two solid phases were formed and confirmed by the Schreinemaker’s wet residue method, and the two were identified as 2Mg(CH3COO)2·3CH3COOH·3H2O and Mg(CH3COO)2·4H2O. However, only one solid phase, Mg(CH3COO)2·4H2O was formed in the ternary Mg(CH3COO)2-CH3COOH·H2O system at 333.1 K. The solubilities of Mg(CH3COO)2 in water-CH3COOH solutions increased with increasing temperature.

The solubility of the ternary system (NH4)2C2O4 + H2O2 + H2O was determined experimentally at 283.15 K and 293.15 K, and the phase diagrams for the system were constructed. In addition, the density...

The Pitzer interaction model, which has been applied successfully to the thermodynamic simulation of electrolyte solutions and electrolyte–nonelectrolyte solutions, was extended to nonelectrolyte–nonelectrolyte solution system. In the present work, the modified Pitzer model was used for calculation and correlation of the ternary CO(NH 2 ) 2 –H 2 O 2 –H 2 O system at 283.15 K. The value of the Pitzer interaction parameters for the ternary system and the thermodynamic solubility product of CO(NH 2 ) 2 ⋅H 2 O 2 were determined using a least-square optimization procedure with coupling activity coefficient and solubility data. The predicted isothermal solubilities agree well with the result obtained from the experiment. The results indicated that the modified Pitzer model could be successfully used to predict the component solubility of the nonelectrolyte–nonelectrolyte system.

The solubility of the quaternary system sodium carbonate + ethanol + hydrogen peroxide + water was determined at 293.15 K using Schreinemaker's wet residue method. The phase diagram was constructed according to the Janeck method. There were three solid phases formed in the quaternary system, which corresponded to Na2CO3·10H2O, Na2CO3·1.5H2O2·H2O, and Na2CO3·2H2O2·H2O. The crystalline region of Na2CO3·1.5H2O2·H2O was larger than that of the other two solids, Na2CO3·10H2O and Na2CO3·2H2O2·H2O. Adding the ethanol into the Na2CO3 + H2O2 + H2O system could promote further crystallization and recover a greater fraction of Na2CO3·1.5H2O2·H2O. The concentrations of sodium carbonate and hydrogen peroxide in the mother liquor after separation from Na2CO3·1.5H2O2·H2O would be lowered as a result of the presence of ethanol. The solubility data and the phase diagram of the quaternary system could provide the fundamental basis and serve as a guide for the preparation of sodium percarbonate.

The solubility data of the calcium acetate-magnesium acetate-water system at 298, 313, and 323 K were measured using the Schreinemaker’s wet residue method, the corresponding phase diagram for the system were constructed. The solid phase in the system at different temperatures was confirmed by the Schreinemaker’s wet residue method, which correspond to Mg(CH3COO)2·4H2O and Ca(CH3COO)2·2H2O. At the studied temperature, no double salt was formed. The crystalline region of Ca(CH3COO)2·2H2O is larger than that of Mg(CH3COO)2·4H2O. The solubility of Mg(CH3COO)2 increases with the increasing of the temperature, while the solubility of Ca(CH3COO)2 decreases with the increasing of the temperature.

Solubility data for the Na2CO3 + Na2SO4 + H2O2 + H2O system at 293 K were determined by Schreinmaker's method. The results were used to construct a phase diagram in the oblique projection according...

In this investigation, solid−liquid equilibrium for the quaternary system sodium carbonate + sodium chloride + hydrogen peroxide + water was studied at a temperature of 293.15 K using the moist solid method. Four solid phases were formed in the quaternary system that correspond to Na2CO3·10H2O, NaCl, Na2CO3· 1.5H2O2·H2O, and Na2CO3·2H2O2·H2O. The solubility fields of four solid phases were observed from the phase diagram. Results indicate that the crystallization field of Na2CO3·1.5H2O2·H2O is very large, the solubility of sodium percarbonate decreases with the increasing of sodium chloride content, and the product of sodium percarbonate can reach a high level. The solubility data and the quaternary phase diagram can provide the fundamental basis for the preparation of sodium percarbonate and optimize the preparing “wet process” and especially can serve as a guide for the preparation of sodium percarbonate with sodium chloride as the salting-out agent.

The extended Pitzer model has been used for calculation and correlation of the ternary NaCl–H2O2–H2O, Na2SO4–H2O2–H2O and the quaternary Na2SO4–NaCl–H2O2–H2O systems at the temperature of 288.15 K. The necessary thermodynamic functions (binary and ternary parameters of interaction and thermodynamic solubility products) have been derived from a least-squares optimization procedure with couples activity coefficient with solubility data and the theoretical solubility isotherms has been plotted. Good agreement with experimental solubility for ternary and quaternary mixtures indicates that the model can be successfully used to predict the component solubility of the electrolyte–nonelectrolytes–water systems containing peroxide. In addition, the Pitzer interaction parameters and the thermodynamic solubility product of 4Na2SO4⋅2H2O2⋅NaCl and Na2SO4⋅0.5H2O2⋅H2O at 288.15 K are obtained.

OBJECTIVE: To investigate the feasibility and efficacy of sight‐guided percutaneous unilateral translaminar facet screw fixation (TLFSF) with interbody fusion for treatment of lower lumbar vertebra diseases. METHODS: Twenty‐nine adult patients with lower lumbar disease underwent sight‐guided percutaneous unilateral TLFSF combined with microsurgical spinal decompression, discectomy, and interbody fusion from June 2007 to June 2008. All 29 patients had low back pain caused by lumbar disc degeneration (20 cases), in situ recurrent lumbar disc herniation (2), primary diskitis (1), lumbar disc herniation with spinal stenosis (3), and first‐degree lumbar degenerative spondylolisthesis (3). Twenty‐three cases had lesions at L (4,5); three at L(5)S(1), one at L (3,4), L (4,5), and two at L (4,5), L(5)S(1). RESULTS: No patient experienced significant postoperative complications. The mean incision length was 4.48 ± 0.55 cm; operative time 1.34 ± 0.22 h; intraoperative blood loss 280 ± 175 mL; and postoperative drainage volume 165 ± 85 mL. Screw position results: type I, 21 cases (23 segments); type II, 7 cases (8 segments); and type III, 1 case (1 segment). Twenty‐eight patients were followed up for 24–60 months (average, 47.5 months). Interbody fusion rate was 93.5%). Postoperative intervertebral height recovered significantly; however, loss of intervertebral height oc urred during follow‐up. CONCLUSION: Sight‐guided percutaneous unilateral TLFSF with interbody fusion for treatment of lower lumbar disease is simple and minimally invasive, with good screw accuracy and security, high fusion rate, and good efficacy. However, specific surgical indications must be strictly followed.

In this investigation, the mutual solubilities for the ternary Na2C2O4 + H2O2 + H2O system were determined at (283.15 and 293.15) K. The phase diagrams of the system were constructed based on the measured solubility. The compound Na2C2O4·H2O2 was confirmed by Schreinemaker's wet residue method. In addition, the density of the system was obtained. At (283.15 and 293.15) K, two solid phases were formed in the ternary Na2C2O4 + H2O2 + H2O system, which corresponded to Na2C2O4 and Na2C2O4·H2O2. The phase diagrams of the ternary system were similar at different temperatures; the solubilities of Na2C2O4 and Na2C2O4·H2O2 in water increased slightly with increasing temperature. The crystalline region of the compound Na2C2O4·H2O2 decreased as the temperature increased, the temperature having little effect on the yield of Na2C2O4·H2O2.

The solubility and density of the equilibrium liquid phase for the ternary K2C2O4 + H2O2 + H2O system were determined experimentally at (283.15 and 293.15) K. The phase diagrams of the system were constructed based on the measured solubility. The compound K2C2O4·H2O2 was confirmed by Schreinemaker's wet residues method. At (283.15 and 293.15) K, two solid phases were formed in the ternary K2C2O4 + H2O2 + H2O system that correspond to K2C2O4·H2O and K2C2O4·H2O2. Results indicated that the phase diagrams of the ternary system are similar at different temperatures. The double salt K2C2O4·H2O2 has a bigger crystallization field than either K2C2O4·H2O or the mixture. The solubilities of K2C2O4·H2O and K2C2O4·H2O2 increase slightly with increasing temperature, while the crystalline region of the compound K2C2O4·H2O2 decreases as the temperature increases.

The scope of experimental research about public management issues is very limited. These issues are also the subjects of general management and economics. For scholoars of public managenment, they need choose experimental research methods based on the characteristics of research issues.