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China has the highest incidence rate of myopia, and the number of teenagers with myopia accounts for more than half of the total number of myopia in the world. In recent years, With the increase of youth night home learning time, the impact of the night lighting environment in the home learning space on eye health has become increasingly obvious. This paper selects 112 home learning spaces of middle school students to carry out the actual measurement of lighting environment parameters and the satisfaction survey of the lighting environment, and through comparative experiments to explore the effects of illuminance, color temperature and lighting methods on eyestrain and visual efficacy. This Study found that under mixed lighting conditions, when the color temperature is 4500k, the illuminance in the range of 500lx-750lx is beneficial to relieve eyestrain and improve visual efficacy; When the illuminance is 500lx, a low color temperature (3500k) can help relieve eyestrain, and a high color temperature (6000k) can improve visual efficacy better. In addition, mixed lighting is better than local lighting for relieving eyestrain and improving visual efficacy. The results will help improve the night lighting environment in the home learning space of middle school students.

The dynamic process of the dissolution of ozone in a countercurrent bubble column is studied for model establishment. Bubble columns have been used widely for ozone contacting in the plant and laboratory. Ozone is produced by oxygen-enriched gas through an ozone generator, and introduced into the bottom of the column equipped with the gas diffuser. The ozone contacting system proceeds for a temporary and unsteady period before reaching steady state. The available ozone dissolution models employed for the description of the dissolved ozone profiles were commonly developed for the steady state. Moreover, oxygen mass transfer is usually neglected in the preceding ozone dissolution models. However, this information is desirable for proper operation of ozone dissolution in a bubble column. Thus, the objective of this study is to model and investigate the dynamic ozone dissolution process in a bubble column with the oxygen mass transfer. The dynamic axial dispersion model proposed is employed to predict the variations of ozone and oxygen concentrations along the column, and the amount of off-gas. The validity of the model is demonstrated by comparing the predicted results with the experimental data. The dynamic model of ozone dissolution is useful and referable for proper prediction of the variables of the ozone contacting system in a bubble column. DOI 10.1061/(ASCE)0733-9372(2002)128:11(1036) CE Database keywords: Ozone; Bubbles; Dynamic models; Mass transfer.

The study was to investigate effects of dietary chlorogenic acid (CGA) on growth performance, flesh quality and serum biochemical indices of grass carp (95.1 ± 0.3 g) ( Ctenopharyngodon idella) fed seven different diets, including control diet, Eucommia ulmoides (EU)-supplemented diet (20 g kg-1) and CGA-supplemented diets containing 100, 200, 400, 600 and 800 mg/kg CGA. Contents of collagen and alkaline-insoluble collagen in muscle and skin were significantly increased by dietary CGA and EU ( p < .05). Total essential amino acids (TEAA) and total amino acids (TAA) in muscle of grass carp fed EU diet or 400, 600 and 800 mg/kg CGA diet were significantly higher than those of fish fed control diet and 100 and 200 mg/kg CGA diet ( p < .05). Fish fed 200-800 mg/kg CGA showed significantly lower muscle crude lipid content than EU, control and 100 mg/kg CGA groups ( p < .05). Fish fed CGA-supplemented diets (100-800 mg/kg) had significantly higher muscle fibre density and lower muscle fibre diameter than control group ( p < .05). In conclusion, supplementation of CGA improved flesh quality of grass carp, and supplemental level of CGA for improving flesh quality and growth was estimated to be 400 mg/kg diet. [ABSTRACT FROM AUTHOR]

The kinetics of the ozonation of polyethylene glycol (PEG) with ultraviolet (UV) radiation in the acid-based electroplating solution of the printed wiring board industry is studied. The substrate prescription of a typical electroplating solution is with pH of 0.18-0.42, [CuS[O.sub.4] * 5[H.sub.2]O] of 200 g/L, [[H.sub.2]S[O.sub.4]] of 60 g/L, and [[Cl.sup.-]] of 0.03 g/L. Certainly, the discarded electroplating solution is hard to treat with the common chemical and biological processes because of its acidic and metallic compositions. In addition, it contains valuable substances suitable for recovery and reutilization. One of the most important processes for reviving it is to remove the aged organic additives such as PEG. A two-step reaction mechanism in terms of ozone A and total organic carbon is proposed to express the reaction kinetics of PEG ozonation with UV radiation with intensity [[I.sub.uv]]. The initial concentration of PEG is 30 mg/L, according to the recipe of a typical electroplating solution, which is equivalent to total organic carbon of 16.3 mg/L. The reaction rate r expressions of the concentrations of the liquid phase ozone [C.sub.ALb], PEG [C.sub.BLb], and intermediates [C.sub.ILb] are [r.sub.A] = -(=d[C.sub.ALb]/dt)=([k.sub.Am] + [k.sub.I][[I.sub.uv]])[C.sub.ALb] - ([k.sub.RI] + [k.sub.RI1][[I.sub.uv]])[C.sub.ALb][C.sub.BLb] - ([k.sub.R2] + [k.sub.RI2][[I.sub.uv]])[C.sub.ALb][C.sub.ILb], [r.sub.B] (=d[C.sub.BLb/dt] = -([k.sub.RI] + [k.sub.RI][[I.sub.uv]] [C.sub.ALb][C.sub.BLb], [r.sub.int] (=d[C.sub.ILb]/dt) = ([k.sub.R1]) + [k.sub.R1] [[I.sub.uv]] [C.sub.ALb][C.sub.BLb] ([k.sub.R2] + [k.sub.RI2][[I.sub.uv]])[C.sub.ALb][C.sub.ILb], with [k.sub.AM] = 0.0036 [s.sup.-1], [k.sub.I] = 4.654 x [10.sup.-5] [s.sup.-1]/(W[m.sup.-2]), [k.sub.RI], = 13.525 [M.sup.-1][s.sup.-1], [k.sub.R2] = 0.751 [M.sup.-1][s.sup.-1], [k.sub.RI1] = 0.683 [M.sup.-1][s.sup.-1]/(W[m.sup.-2]), and [k.sub.RI2] = 0.042 [M.sup.-1][s.sup.-1]/(W[m.sup.-2]). These reaction kinetic expressions are useful and referable for the proper design of an ozonation system with UV radiation for the treatment of PEG in the printed wiring board electroplating solution.

Abstract: In this investigation, the tribological performance of (Cu42Zr42Al8Ag8)99.5Si0.5 bulk metallic glass (BMG) was evaluated and compared with that of hardened S45C medium carbon steel. Three of classes of specimen were used in wear tests; they were as-cast BMG, annealed BMG and hardened S45C. Wear tests were conducted using a cylinder-on-plate Cameron-Plint TE77 reciprocating friction machine. The worn surfaces of wear specimens are observed by scanning electron microscopy (SEM), and the chemical compositions of localized regions are characterized by energy dispersive spectroscopy (EDS). The results indicate that the dominant wear mechanisms of the as-cast BMG and annealed BMG are delamination under dry sliding conditions. In contrast, the dominant wear mechanism of hardened S45C is adhesive wear. Under water-lubricated conditions, most of the worn scars are formed by abrasive wear. Although the hardness of as-cast BMG equals that of hardened S45C, the wear performance of as-cast BMG is poorer than that of hardened S45C. However, the annealed BMG exhibited the best wear performance, because of hardening by nanocrystal precipitation. This precipitation hardening effect reduces the depth of penetration by wear particles during sliding. Oil-lubricated conditions were established using three oils, and paraffin mineral (MN) base oil was found to yield the greatest wear volume for as-cast BMG. The wear loss of the as-cast BMG test in paraffin MN base oil was the highest among all of the specimens, perhaps because of tribochemical reaction wear. However, the annealed BMG exhibited excellent wear performance in paraffin MN base oil. [Copyright &y& Elsevier]

In this study, the pilot apparatus combined with sand filtration, ozonation and ultrafiltration was established. Wastewater from the secondary treatment effluent in the new-developed community was taken as the sample for looking into the feasibility of domestic wastewater reuse and recycling. The test results by sand filtration, sand filtration/ultrafiltration, sand filtration/ozonation, and sand filtration/ultrafiltration/ozonation were compared for looking for appropriate treatment processes applied in the domestic wastewater reuse and recycling. Finally, cost analysis was carried out and sand filtration/ozonation process was suggested to be one of the best processes. The total cost is about 0.1–0.32 $USD per cubic meter of produced water by considering the capital and operation cost for five years in the small domestic wastewater treatment plant (50–750 CMD). [ABSTRACT FROM AUTHOR]

This research focused on the biological treatment of high-strength organic nitrogen wastewater, and presented the results from the nitrification and denitrification of an actual industrial wastewater using anoxic/aerobic process. The opto-electronic industrial wastewater often contains a significant quantity of organic nitrogen compounds and has a ratio over 95% in organic nitrogen (Org-N) to total nitrogen (T-N). In this study, a 2-stage anoxic/aerobic process was established and evaluated the efficiency of wastewater treatment. Raw wastewater from an actual TFT-LCD manufacturing plant was obtained as the sample for looking into the feasibility of opto-electronic industrial wastewater treatment. After toxicity identification evaluation (TIE) test of raw wastewater, the inhibition was related to organic nitrogen (TMAH, MEA) and unionized ammonia (free ammonia, NH3) with high pH. Therefore, pH control is important for biological treatment of high-strength organic nitrogen industrial wastewater. Besides, hydraulic retention time (HRT) and mixed liquor recycled rate (MLR) were controlled independently to distinguish between the effects of these two factors. Under suitable HRT (>1.7 d) and mixed liquor recycled rate (<4Q), effluent of NH4-N, NO3-N + NO2-N, and COD can fall below 20 mg/L, 30 mg/L, and 80 mg/L. The anoxic/aerobic process removed 92–98% of the carbon source, and approximately 80% of TKN, 70% of T-N. [ABSTRACT FROM AUTHOR]

Explores functional improvement by adding various kinds of metallic ions in the ozonation of 2-chlorophenol solution. Reaction rate when metallic ions were added; Data indicating the best result was obtained by using manganese ions, followed by iron and titanium ions; Finding suggesting the ozone self-decomposition coefficient is highly dependent on the reaction rate constant for ozonation of 2-chlorophenol; View that the improvement of reaction was relevant to the mechanism of reaction between ozone and metallic ions; Effect of adding manganese ions.

Reports on the establishment of a pilot plant that combined ozonation with sand filtration. Use of wastewater from the secondary effluent as sample for looking into the feasibility of domestic wastewater recovery and recycling; Clean water tests for ozone transfer efficiency; Hydraulic analysis of bubble column reactor.

Examines the kinetics of surface wave suppression in film flow down a vertical plane. Derivation of an equation relating the average rate of disturbance kinetic energy change; Evaluation of terms in the equation; Elucidation of the physical mechanism of vertical film flow stabilization.

Analyzes the stability of a viscous liquid film flow down an inclined plane that oscillates in the direction parallel to the flow. Use of a Chebyshev series solution with the Floquet theory; Manifestation of film instability in long surface waves when the inclined plane is stationary; Factors that determine film stabilization.

The catalytic decomposition of ozone in the presence of water vapor at the relative humidity (RH) of about 90 % was investigated by using a tubular fixed‐bed reactor. The performance tests and reaction kinetic studies were conducted for catalyst, i.e., Pt/γ ‐Al2O3 (symbolized as Dash‐220). The experiments were carried out at various constant reaction temperatures (298 ∼ 323 K) and space velocities (24,000 ∼ 44,000 hr‐1). About 75 % decomposition efficiencies of ozone with inlet concentration of about 0.17 mol/m3 was achieved at catalyst contact time of 0.15 sec (space velocity of 24,000 hr‐1), reaction temperature of 323 K and RH of about 90 % for the Dash‐220 catalyst. However, about 97% decomposition efficiencies of ozone without the presence of water vapor at the same reaction conditions. The results indicated that the Dash‐220 catalyst with the presence of water vapor gave lower performance of ozone decomposition than without the presence of water vapor can be achieved at the same reaction conditions. For the reaction kinetics, it was found that the pseudo‐first‐order chemical reaction rate equation was appropriate for the catalytic decomposition of ozone in the presence of water vapor investigated in this study. The apparent activation energies for the decomposition reaction of ozone using the Dash‐220 catalyst in the presence of water vapor at RH of 90 % is 19.32 kJ mol‐1. The corresponding pre‐exponential factor is 0.0041 mol/(s g‐catalyst (mol/m3)). [ABSTRACT FROM PUBLISHER]

Demonstrates that three-dimensional unstable waves in a vertical film can be suppressed by use of the Chebyshev series solution with Floquet theory. Unstable nature of a vertical film flow with respect to long surface wave disturbances.

In this work, three different states of Mg-9.1Y-1.8Zn alloys including as-cast, extruded and swaged were prepared by semi-continuous casting, extrusion and swaging processes, respectively. Their compositions, microstructures and hydrogen storage properties were investigated. The results show that Mg-9.1Y-1.8Zn alloys in three different states are all composed of Mg and long-period stacking ordered (LPSO) phases. The LPSO phases occurs to break and decompose after hydrogenation and in-situ forms the YH χ(χ = 2,3) nano-hydrides. The nano-hydrides can be used as in-situ catalysts to improve the hydrogen storage properties of alloys. Meanwhile, many nanocrystalline grains appear in the core of alloy after swaging, and the average grain size ranges from 80 to 200 nm. The presence of nanocrystals may increase the specific surface area of alloy, facilitating the diffusion and absorption of hydrogen. Comparatively, the swaged alloy exhibits the largest hydrogen storage capacity and excellent hydrogen sorption kinetics relative to other states of alloys. • The as-cast, extruded, and swaged Mg-9.1Y-1.8Zn alloys were prepared. • The LPSO phases decomposes and in-situ forms YH χ(χ = 2,3) hydrides upon hydrogenation. • The YH χ(χ = 2,3) hydrides present in-situ catalytic and pinning effects on Mg matrix. • The swaged alloy exhibits the highest hydrogen storage capacity. [ABSTRACT FROM AUTHOR]

In this work, the as-cast Mg-rich Mg 98.5 Gd 1 Zn 0.5 and Mg 98.5 Gd 0.5 Y 0.5 Zn 0.5 alloys are prepared by the semi-continuous casting method, and their hydrogen storage performance and catalytic mechanisms are investigated by experimental and first-principles calculations approaches. The results show that the LPSO phases decompose and in-situ form the RE(Gd/Y)H x (x = 2,3) nano-hydrides upon hydrogenation. These nano-hydrides not only serve as the in-situ catalysts to promote the hydrogen ab/desorption of Mg matrix, but also present the pinning effect to inhibit the growth of Mg / MgH 2 grains during hydrogenation and dehydrogenation. Comparatively, the two alloys exhibit the similar hydrogen absorption kinetics, while the hydrogen desorption kinetics of Mg 98.5 Gd 1 Zn 0.5 is superior to that of Mg 98.5 Gd 0.5 Y 0.5 Zn 0.5. The first-principles calculations reveal that the GdH 2 and YH 2 hydrides exhibit different catalytic effects on weakening the bond strength of H–H within H 2 and Mg–H within MgH 2 , which interprets well the differences in the hydrogen ab/desorption kinetics between Mg 98.5 Gd 1 Zn 0.5 and Mg 98.5 Gd 0.5 Y 0.5 Zn 0.5 alloys. • The Mg-rich Mg-Gd-Zn and Mg-Gd-Y-Zn alloys are prepared by semi-continuous casting. • The LPSO phases decompose and in-situ form RE(Gd / Y)H x (x = 2,3) upon hydrogenation. • The RE(Gd/Y)H x (x = 2,3) show in-situ catalytic and pinning effects on Mg alloys. • The desorption rate of Mg 98.5 Gd 1 Zn 0.5 is faster than that of Mg 98.5 Gd 0.5 Y 0.5 Zn 0.5. • The GdH 2 and YH 2 both weaken the bond strength of H–H within H 2 and Mg–H with MgH 2. [ABSTRACT FROM AUTHOR]

Objective: We aimed to investigate the effect of a code stroke system on the development of poststroke epilepsy., Methods: We retrospectively analyzed consecutive patients treated with IV thrombolysis under or outside the code stroke system between 2003 and 2012. Patients were followed up for at least 2 years or until death. Factors with p < 0.1 in univariate comparisons were selected for multivariable logistic and Cox regression., Results: A total of 409 patients met the eligibility criteria. Their median age at stroke onset was 75 years (interquartile range 64-83 years); 220 (53.8%) were male. The median follow-up duration was 1,074 days (interquartile range 119-1,671 days). Thirty-two patients (7.8%) had poststroke seizures during follow-up, comprising 7 (1.7%) with acute symptomatic seizures and 25 (6.1%) with late-onset seizures. Twenty-six patients (6.4%) fulfilled the definition of poststroke epilepsy. Three hundred eighteen patients (77.8%) were treated with the code stroke system while 91 (22.2%) were not. After adjustment for age and stroke etiology, use of the code stroke system was associated with decreased odds of poststroke epilepsy (odds ratio = 0.36, 95% confidence interval 0.14-0.87, p = 0.024). Cox regression showed lower adjusted hazard rates for poststroke epilepsy within 5 years for patients managed under the code stroke system (hazard ratio = 0.60, 95% confidence interval 0.47-0.79, p < 0.001)., Conclusion: The code stroke system was associated with reduced odds and instantaneous risk of poststroke epilepsy. Further studies are required to identify the contribution of the individual components and mechanisms against epileptogenesis after stroke., Classification of Evidence: This study provides Class III evidence that for people with acute ischemic stroke, implementation of a code stroke system reduces the risk of poststroke epilepsy., (© 2018 American Academy of Neurology.)