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The perchlorinated zinc ash contains zinc metal, a small amount of heavy metals and harmful elements chlorine. In order to reduce the chlorine content in the perchlorinated zinc ash, the removal effect of water washing and ammonia washing on the impurities in the perchlorinated zinc ash was compared and studied. The influence of ammonia concentration, liquid volume to solid mass ratio and washing temperature on the precipitation rate of zinc in the ammonia washing process was investigated by single factor test, and the optimal ammonia washing conditions were determined by orthogonal test. The results show that the removal rates of Cl,Na and K are more than 99% and the precipitation rate of Zn is 98.7% under the conditions of ammonia concentration of 0.05%, liquid volume to solid mass ratio of 6 mg/1 L and reaction temperature of 30 °C. [ABSTRACT FROM AUTHOR]

To investigate the adsorption kinetics and thermodynamic adsorption mechanism and laws of dry flue gas desulfurization, we prepared a new adsorbent by loading Cr, Cu, and Zn on TiO2-loaded multiwalled carbon nanotubes. Desulfurization experiments were also carried out. In this study, three kinds of samples were used for simulation and diffusion processes in the dynamic adsorption of different SO2 volume fractions in flue gas and thermodynamic model analysis of different temperatures in flue gas. Results show that the diffusion coefficient of SO2 in three kinds of samples ranges from 10−16 to 10−14 m2 s−1, and the diffusion may be dominated by configuration diffusion. The intraparticle diffusion model predicts that the performance improves with an increase in the SO2 volume fraction and a shift of adsorption time. This finding indicates that an increase in SO2 volume fraction and a change in adsorption time increase the Kundsen diffusion specific gravity and decrease the configuration diffusion specific gravity, thereby increasing the SO2 diffusion resistance, which becomes faster than the activation energy barrier resistance in the catalytic oxidation reaction. Thus, the diffusion resistance specific gravity increases in the total resistance of the diffusion reaction. One possible mechanism of the adsorption process is the transition to surface reaction control at the early stage of adsorption to joint control of late diffusion and surface reactions. Adsorption thermodynamics studies show that SO2 adsorption by three adsorbents is a spontaneous, exothermic, and entropic reduction process, and the increase in temperature is inconducive for SO2 adsorption in three samples.

Background: The amygdala has been implicated in obsessive-compulsive disorder (OCD), a common, disabling illness. However, the regional distribution of anatomic alterations in this structure and their association with the symptoms of OCD remains to be established. Methods: We collected high-resolution 3D [T.sub.1]-weighted images from 81 untreated patients with OCD and no lifetime history of comorbid psychotic, affective or anxiety disorders, and from 95 age- and sex-matched healthy controls. We extracted the volume of the central nucleus of the amygdala (CeA) and the basolateral complex of the amygdala (BLA) and compared them across groups using FreeSurfer 6.0. In exploratory analyses, we evaluated other subnuclei, including the cortical medial nuclei, the anterior amygdaloid area, and the corticoamygdaloid transition area. Results: Patients with OCD had reduced amygdala volume bilaterally compared with healthy controls (left, p = 0.034; right, p = 0.002). Volume reductions were greater in the CeA (left: -11.9%, p = 0.002; right: -13.3%, p < 0.001) than in the BLA (left lateral nucleus: -3.3%, p = 0.029; right lateral nucleus: -3.9%, p = 0.018; right basal nucleus: -4.1%, p = 0.017; left accessory basal nucleus: -6.5%, p = 0.001; right accessory basal nucleus: -9.3%, p < 0.001). Volume reductions in the CeA were associated with illness duration. Exploratory analysis revealed smaller medial (left: -15.4%, p < 0.001, [[eta].sup.2] = 0.101) and cortical (left: -9.1%, p = 0.001, [[eta].sup.2] = 0.058; right: -15.4%, p < 0.001, [[eta].sup.2] = 0.175) nuclei in patients with OCD compared with healthy controls. Limitations: Although the strict exclusion criteria used in the study helped us to identify OCD-specific alterations, they may have limited generalizability to the broader OCD population. Conclusion: Our results provide a comprehensive anatomic profile of alterations in the amygdala subnuclei in untreated patients with OCD and highlight a distinctive pattern of volume reductions across subnuclei in OCD. Based on the functional properties of the amygdala subnuclei established from preclinical research, CeA impairment may contribute to behavioural inflexibility, and BLA disruption may be responsible for altered fear conditioning and the affective components of OCD., Introduction Obsessive-compulsive disorder (OCD) has a lifetime prevalence of 1% to 3% (1) and causes significant distress and functional impairment. (2) Dysregulation in the cortico-striatothalamo-cortical (CSTC) circuitry has been proposed [...]

The flexible mode of operation of coal-fired units can accommodate large-scale renewable power integration into the grid, providing more grid capacity. The flexibility transformation of coal-fired units in thermal power plants can be achieved through main steam extraction and reheated steam extraction. A 300 MW subcritical unit, 600 MW subcritical unit and 660 MW ultra-supercritical unit with six flexible operation modes were chosen as the research model to investigate the thermal adaptability for flexible operation. The results show that from the perspective of the source of steam extraction, the main steam extraction scheme is suitable for the flexible adjustment of peak load capacity, and the reheated extraction scheme is suitable for the flexible operation of low load and high thermal efficiency. Moreover, from the perspective of thermal performance adaptability, the 600 MW unit has a wider load regulation capacity than the 300 MW and 660 MW units, and is suitable as the peak shaving unit. This work can provide theoretical guidance for different types of coal-fired units in choosing flexible operation schemes. [ABSTRACT FROM AUTHOR]

Molten salt and supercritical CO2 (sCO2) have been selected as the two most promising heat transfer fluids in the 3rd generation of solar thermal power generation, so it is very important to study their heat transfer and flow characteristics for the design of heat exchanger. This research studies thermohydraulic performance of molten salt and sCO2 in a printed circuit heat exchanger (PCHE) with different channel configurations. A PCHE unit with straight channel for molten salt and discontinuous fin for sCO2 was selected for the fin shape optimization of sCO2 side. Results show that the newly proposed Fin II channel can reduce the flow resistance of sCO2 compared with the airfoil Fin I, and Fanning friction factor can be decreased by 11.93% at the expense of Colburn factor decreased by 2.24%. The mechanism of heat transfer enhancement is analyzed by using field synergy principle, and the results show that the temperature field, velocity field and pressure field have better synergy in the Fin II channel. The optimal finned channel improves the comprehensive performance of PCHE, which contributes to the third generation of solar thermal power generation. [ABSTRACT FROM AUTHOR]

Excellent morphology and low harmful defect states of the absorber layer are essential to fabricate the high‐performance Cu2ZnSn(S, Se)4 (CZTSSe) devices. Herein, the annealing time of precursor films in air is proved to have much impact on the quality of absorber layer and the performance of devices. Appropriately extending the air‐annealing time can promote the diffusion of Na into films and O absorption on the surface of precursor films, boost the growth of crystal grain, and lessen the harmful defect density and band‐tailing states of absorber. The appropriate extension of air‐annealing time also regulates the electrical properties of the absorber. The efficiency of CZTSSe devices is enhanced from 6.92% (1 min) to 10.1% (7 min), with the decreased VOC, Def. These enhanced properties demonstrate that regulating the air‐annealing time of precursor films can be a simple and direct way for improving the performance of CZTSSe devices. [ABSTRACT FROM AUTHOR]