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Reactive adsorption desulfurization over metal oxides adsorbents was carried out to remove the sulfur of real fluid catalytic cracking gasoline and model gasoline in a batch reactor at low pressures in the presence of hydrogen. The results show that Ni appearing after reduction and higher temperature leads to a significant improvement in the desulfurization ability of the adsorbents. When the initial concentration of thiophene in the model gasoline raised the sulfur, removal rate decreased while the adsorption capacity of the adsorbents increased and the maximum sulfur removal rate and sulfur adsorption capacity were 86.33% and 13.72 mg/g, respectively. [ABSTRACT FROM PUBLISHER]

The oxides adsorbent of NiO/ZnO-Al2O3-SiO2was prepared by a co-precipitation method. The adsorbent can be used for the desulfurization of thiophene inn-hexane as model gasoline. Conditions of the reactive adsorption desulfurization in model gasoline were studied. Adsorption kinetics were found to follow a pseudo-first-order better than pseudo-second-order model. Equilibrium isotherms for the adsorption of thiophene over metal oxides adsorbents were analyzed by Freundlich and Langmuir isotherm models using a non-linear regression method. Further, Langmuir isotherm represented the equilibrium adsorption data best at all temperatures. [ABSTRACT FROM AUTHOR]

The oxides adsorbent of NiO/ZnO-Al2O3-SiO2was prepared by a co-precipitation method. NiO/ZnO-SiO2-Al2O3is an effective adsorbent for reactive adsorption desulfurization of fluid catalytic cracking gasoline. The reaction conditions, such as reaction temperature, total pressure, weight hourly space velocity, and volume ratio of hydrogen to oil for desulfurization over NiO/ZnO-SiO2-Al2O3in a fixed-fluidized bed reactor were investigated. With the optimum conditions, the sulfur content of FCC gasoline can be decreased from 180 to 11.6 mg·L−1, and the loss of olefin content of gasoline product is 1.05%, the research octane number loss of gasoline product is only 1.3 unit. [ABSTRACT FROM PUBLISHER]

Mn0·4/Co0·1Ce0·45Zr0·45OX was prepared by introducing Co into Mn/Ce-ZrOX and was used for low temperature selective catalytic reduction (SCR) of NO with NH3 at different reaction conditions. X-ray diffraction, temperature programmed desorption and temperature programmed reduction were performed to character the physicochemical property of the catalyst and supports. Experimental results showed that the introduction of Co increased the surface acidity and improved the redox properties of the catalysts. Mn0·4/Co0·1Ce0·45Zr0·45OX produced a good activity at low temperature, and the NO conversion of the catalyst was >90% in the temperature range of 120-220°C. Furthermore, Mn0·4/Co0·1Ce0·45Zr0·45OX showed an excellent resistance to SO2 and H2O at different reaction conditions. The catalytic activity was stable during the treatment of SO2 and H2O, and the activity recovered to the original level after cutting off the injection of SO2 and H2O. Therefore, Mn0·4/Co0·1Ce0·45Zr0·45OX is a promising catalyst for the SCR in NO by ammonia. [ABSTRACT FROM AUTHOR]

The liquid adsorption separation ofn-paraffins in naphtha withn-pentane as the desorbent was investigated and the subsequent recycle ofn-pentane was simulated by Aspen Plus. The optimal operation conditions for both the adsorption and desorption processes were studied. Thenn-pentane was recycled by simulated rectification; the raffinate bottom oil rich in non-normal hydrocarbons and the desorption bottom oil rich in normal hydrocarbons were obtained. As compared to the naphtha before the adsorption-recycle process, the ethylene yield would rise by 15.76% by employing the desorption bottom oil as the feed for the ethylene cracking process and the octane number of the raffinate bottom oil would rise by 20 units. [ABSTRACT FROM PUBLISHER]

The selective oxidative desulfurization was conducted with a feedstock of model gasoline consisting of thiophene and n-octane in an H2O2·HCOOH oxidative system over a Ti-MCM-41 catalyst. The operations were designed by the orthogonal design method with an L9 (34) table. Experimental results show that the factors influencing the rate of desulfurization are reaction temperature, the reaction time, and the volume percent content of the hydrogen peroxide in order. Under the optimized operation conditions over Ti-MCM-41 catalyst: H2O2 volume fraction of 3% (v), reaction time of 40 min and reaction temperature of 50°C, the removal ratio of thiophene was 95.6%, and the gasoline yield was 98.7%. The activity of the catalyst has no dramatic deactivation after reusing it five times. In addition, the kinetics study indicates that this reaction is a pseudo first-order reaction with the activation energy of Ea = 40.18 kJ/mol. [ABSTRACT FROM PUBLISHER]

Pd/Al2O3 catalysts were prepared by wet impregnation using K2PdCl4, (NH4)2PdCl4, and Pd(NO3)2 as precursors. All catalysts were characterized by means of inductively coupled plasma-atomic emission spectroscopy (ICP-AES), temperature-programmed reduction (TPR), X-ray diffraction (XRD), and CO chemisorption. The results obtained in the hydrogenation of cumene hydroperoxide (CHP) to α-cumyl alcohol (CA) showed that Pd/Al2O3 catalyst prepared from Pd(NO3)2 exhibited the highest turnover frequency (TOF) value and the greatest deactivation extent, whereas Pd/Al2O3 catalyst prepared from (NH4)2PdCl4 displayed the lowest TOF value but the best stability. [ABSTRACT FROM AUTHOR]

The physicochemical properties of hydrogenated diesel fuel and its fractions produced by hydro-refining, hydro-upgrading, and hydro-cracking were analyzed. The lubricity of diesel fuel and its fractions were measured by a high-frequency reciprocating rig. The relationships of lubricities between the fractions were discussed. The prediction model for the lubricity of hydrogenated diesel with a sulfur content below 200 μg/g was established by using the stepwise linear regression method. The coefficient, R, reached up to 0.981, and the relative error of the predicted value to the actual value was less than 7%. According to the coefficients of the prediction model, the lubricity of ultra-low sulfur diesel with high kinematics viscosity, high nitrogen content, and low cycloparaffins content under the condition of deep hydrogenation was relatively inferior. The model could well predict the lubricity of the ultra-low sulfur diesel fuel and hydro-fining diesel fuel. [ABSTRACT FROM AUTHOR]

Objective: To preliminarily examine the feasibility and outcome of single-port laparoscopic radical prostatectomy with full-length urethral preservation (FLUP-SPRP). Method: This study was a prospective case series study. A total of 25 patients with prostate cancer who met the enrollment criteria and agreed to this surgical procedure from March 2022 to December 2022 were collected at the Department of Urology, the Second Affiliated Hospital of Nanjing Medical University. The age of the patients was (67.2±7.6) years (range: 61 to 76 years). This novel procedure was performed by an experienced surgeon who performed single hole radical prostatectomy skillfully. Patient urinary control, tumor control, and related surgical complications after surgery were regularly monitored. Postoperative urinary control was evaluated using the daily amount of urine pad, 0 to 1 piece of urine pad was to restore urinary control, and 0 to 1 piece of pad within 24 hours after catheter removal was immediate urinary control. Result: All prodecures were successfully completed without transit to open surgery. The surgical time was (128.4±22.4) minutes (range: 100 to 145 minutes), the intraoperative blood loss was (68.2±13.7) ml (range: 50 to 120 ml). The urethral injury occurred in 4 cases during surgery and was repaired by sutures. The urinary control recovery rates within 24 hours, 1 week, 4 weeks, and 7 weeks after surgery were 80.0%, 84.0%, 92.0% and 100%, respectively. Postoperative large section pathology revealed 1 case with a positive basal margin of the prostate and negative margins of all prostate glands around the urethra. Postoperative complications included urinary tract infection in 3 cases, urodynia in 2 cases, and acute urinary retention in 1 case. MRI follow-up 3 months after surgery showed normal anatomy of the bladder and urethra. The follow-up values of prostate specific antigen at 3 and 6 months after surgery were less than 0.1 μg/L. Conclusions: The preliminary results of this study indicate that the FLUP-SPRP procedure is safe and feasible. The early results of postoperative urinary control and oncology are as expected.

We aimed to assess parameters reflecting left ventricular function by dual-source computed tomography (DSCT) with echocardiography (ECG) as control. Fifty-eight patients with coronary heart disease (CHD) were recruited from January to June 2011; 29 CHD patients had type II diabetes. All patients were assessed by cardiac DSCT and ECG examination. DSCT and ECG correlated well for ejection fraction (EF) (r = 0.70), end-systolic volume (ESV) (r = 0.87), stroke volume (SV) (r = 0.83), and end-diastolic volume (EDV) (r = 0.90). The mean ESV and EDV values measured by the two methods in CHD patients with type II diabetes were higher than those in non-diabetic patients, whereas the mean EF was lower. DSCT is an accurate and practical method for assessing left ventricular function.

Our aim was to better understand and improve the accuracy of the preoperative diagnosis of intraspinal MM by a combined analysis of MR imaging and pathologic findings. All 5 patients had undergone unenhanced and contrast-enhanced MR imaging examinations. All tumor samples had immunohistochemical reactions to HMB-45, vimentin, S-100, EMA, and Leu-7 antibodies. All 5 cases were located in the intradural extramedullary compartment. Two cases had multifocal lesions, and 3 cases were solitary. Two cases showed homogeneously strong enhancement, and 3 cases showed moderate enhancement on contrast-enhanced T1WI. The tumor cells had positive reactions to HMB-45, vimentin, and S-100 antibodies. MR imaging plays an important role in the detection and diagnosis of intraspinal MM. Final diagnosis should be based on histopathology and IHC examinations.

Objective: To evaluate the MRI in the differential diagnosis of acute non-traumatic vertebral collapse., Methods: Sixty-eight cases were retrospected. All cases were studied with sagittal T1-weighted MR images, T2-weighted MR images, gadolinium-enhanced T1-weighted MR images, and axial T1-weighted MR images. Twelve of 68 were performed extra coronal T1-weighted MR images and 22 with additional axial gadolinium-enhanced T1-weighted images., Results: The causes of vertebral collapse were: (1) osteoporosis (n = 31), their images showed retropulsion of bony fragments of collapsed vertebral body which kept the normal signal into the spinal canal as the distinctive sign; (2) metastatic tumor (n = 30), their images showed destructions of pedicles of vertebral and epidural mass as the distinctive sign, and hyperintense or mixed hyperintense signal on T2WI and enhanced T1WI of compressed vertebrae; and (3) multiple myeloma (n = 7), their images showed long T1WI and long T2WI, without destruction of pedicle and epidural mass in compressed vertebrae., Conclusion: MRI is useful to the differentiations of the non-traumatic vertebral collapse in aged.