Simultaneous tectonic Descemet stripping endothelial keratoplasty and tectonic Bowman layer transplant for the management of corneal perforation

AIM:To report the outcomes of three cases of corneal perforation managed with simultaneous tectonic Descemet stripping endothelial keratoplasty(t-DSEK)and tectonic Bowman layer transplant(t-BLT)as an alternative to tectonic penetrating keratoplasty(t-PKP).METHODS:Three eyes of three patients receiving simultaneous t-DSEK and t-BLT for corneal perforation were included.The technique for DSEK was modified depending on individual requirements.The t-BLT technique was standardised using an 8 mm graft and fixated with a running suture.Success was measured by the ability of this procedure to close a corneal perforation.RESULTS:All three cases achieved tectonic eye globe restoration and remained stable during the minimum 3-month observation period.Reinterventions were relatively common:2 cases required amniotic membrane transplant for persistent epithelial defects.One case required DSEK rebubbling.One case developed angle closure glaucoma requiring surgical peripheral iridectomy.CONCLUSION:Simultaneous t-DSEK and t-BLT may be a useful strategy for the management of corneal perforation as an alternative management to t-PKP for selected cases.

A simulation study of a windowless gas-stripping room in an E//B neutral particle analyzer

The neutral particle analyzer(NPA)is one of the crucial diagnostic devices in a Tokamak facility.The stripping unit is one of the main parts of the NPA.A windowless gas-stripping room with two differential pipes has been constructed in a parallel electric and magnetic fields(E//B)NPA.The pressure distributions in the stripping chamber are simulated by ANSYS Fluent together with MolFlow+.Based on the pressure distributions obtained from the simulation,the stripping efficiency of the E//B NPA is studied using GEANT4.Hadron reaction physics is modified to track the charge state of each particle in a cross-section-based method in GEANT4.The transmission rates(R)and stripping efficiencies f_(+1)are examined for particle energies ranging from 20 to 200 keV with the input pressure(P_(0)),ranging from 20 to 400 Pa.According to the combined global efficiency,R×f_(+1),P_(0)=240 Pa is obtained as the optimum pressure for the maximum global efficiency in the incident energy range investigated.

Studies on Alternating Pulse Current-Chronopotentiometric Stripping Analysis

Alternating pulses current - chronopotentiometric stripping analysis (APC-CPSA) is a new method as a variant of chronopotentiometric stripping analysis (CPSA). During the stripping step an alternating pulse current with a high frequency in a square wave mode is imposed on the electrode system. Thus, tau and sensitivity of APC-CPSA is increased a lot. The tau, E similar to t equation and its reciprocal derivative equation for APC-CPSA are derived and verified by the experimental results.

New insights into “dead lithium” during stripping in lithium metal batteries

Lithium (Li) metal attributes to the promising anode but endures the low Columbic efficiency (CE) and safety issues from the inactive Li accumulation. The metallic Li which is isolated from the lithium anode (named dead Li^(0)) consists the major component of the inactive Li. We systematically and meticulously investigated the formation and evaluation of dead Li^(0) during stripping process from electron transfer, the oxidation of Li^(0) to Li^(+) and the diffusion of Li^(+) through solid electrolyte interphase (SEI). The above-mentioned processes were regulated by adjusting the contact sites of electron channels, the dynamic rate of conversion from Li^(0) to Li^(+), and the structure as well as components of SEI. The design principles for achieving less dead Li^(0) and higher CE are proposed as a proof of concept in lithium metal batteries. This new insight sheds a comprehensive light on dead Li^(0) formation and guides the next-generation safe batteries for future application.

Removing ammonia from skim by air stripping with rotating packed bed

Based on the effects of skim components on ammonium removal as well as the current processing technology, a new process-intensified technology of removing ammonia from skim by air stripping on rotating packed bed was proposed. The experiments were conducted on a wave-thread packed Rotating Packed Bed(RPB) under atmospheric pressure, suggesting that, in terms of order of importance, the ammonium concentration of feed-stock(x_w), the average ultra-gravity factor(β), feed-stock flux(L), and gas flux(G) had significant impact on ammonium removal rate(η) and the ammonium concentration of products(x_D). In the experiment, mass-transfer coefficient in gas phase(k_ya_e) increases with the increase of β, G/L, and L. The ammonium concentration of products decreases with the increase of β, G/L and the increase of L. The ammonium concentration of products would be as low as ~0.10% and the ammonia removal rate would be 63.21% when skim temperature was 25 °C, x_w0.28%, β 133.2, and G/L 15.0 m^3·L^(-1). Experiment results indicated that the proposed technology for removing ammonium from skim on a rotating packed bed would be a new process-intensified technique compared with traditional aeration process and centrifugal atomization method.

Study on Semi-Continuous Technology System for Soft Material Stripping in Large Surface Mines

Continuous and semi-continuous mining technology has become the main trend of modern surface mines in the world. According to the deposit characteristics of coal basin in China and Chinese situation,this paper discussed the new semi-continuous technology── shovel - transfer wagon-belt conveyor and its application prospect in large surface coal mines in China.

Visual acuity and endothelial cell density with respect to the graft thickness in Descemet's stripping automated endothelial keratoplasty: one year results

AIM: To evaluate the visual acuity and endothelial cell density according to the thickness in Descemet’s stripping automated endothelial keratoplasty(DSAEK)one year after surgery.METHODS: DSAEK patients’ data were reviewed. Thirty seven eyes of 37 patients who underwent DSAEK for pseudophakic bullous keratopathy(PBK) were included in this study. Graft thickness was measured with optical coherence tomography(OCT) 12 mo after DSAEK. Eyes were divided into 3 groups based on the graft thickness:thick(】200 μm), medium-thick(150-200 μm) and thin(【150 μm). Best corrected visual acuity(BCVA),endothelial cells density(ECD) and complications were assessed and comparisons were done between groups.RESULTS: Median thickness of postoperative grafts was 188(range 73-317 μm). There was no significant difference in age, sex, preoperative BCVA, or follow-up period between DSAEK groups. At postoperative 12 mo,mean BCVA was 0.28±0.10 in thick graft group, 0.52±0.08 in medium-thick graft group, and 0.72 ±0.06 in thin graft group. Thin grafts showed better postoperative BCVA as compared with the medium-thick and thick grafts(P =0.001). Thick graft group had 1637.44 ±88.19-mm2,medium thick graft had 1764.50±34.28-mm2 and thin graft group had 1845.30 ±65.62-mm2. Thin graft group had better ECD at 12 mo after surgery(P =0.001).CONCLUSION: Thin grafts after DSAEK ensure better visual rehabilitation. Eyes with thin grafts had significantly lesser loss of ECD compared to eyes withmedium-thick and thick grafts one year after surgery.

Surface Analysis of Chemical Stripping Titanium Alloy Oxide Films

The chemical stripping method of titanium alloy oxide films was studied. An environment friendly solution hydrogen peroxide and sodium hydroxide without hydrofluoric acid or fluoride were used to strip the oxide films. The morphologies of the surface and cross-section of the oxide films before and after the films stripping were characterized by using scanning electron microscopy （SEM）. The microstructure and chemical compositions of the oxide films before and after the films stripping were investigated by using Raman spectroscopy （Raman） and X-ray photoelectron spectroscopy （XPS）. It was shown that the thickness of the oxide film was in the range of 5-6 μm. The oxide films were stripped for 2 to 8 min in the solution. Moreover, the effect of the stripping time on the efficiency of the film stripping was investigated, and the optimum stripping time was between 6-8 min. When the stripping solution completely dissolved the whole film, the α/β microstructure of the titanium alloy Ti-10V-2Fe-3Al was partly revealed. The stripping mechanism was discussed in terms of the dissolution of film delamination. The hydrogen peroxide had a significant effect on the dissolution of the titanium alloy anodic oxide film. The feasibility of the dissolution reaction also was evaluated.

Conceptual design of energy-saving stripping process for industrial sour water

Sour water contains ammonia,carbon dioxide,and hydrogen sulfides,producing from oil refining,coking,and coal gasification.To reduce the energy consumption in sour water stripping,a novel process is proposed which integrates with the bottom flashing mechanical vapor recompression heat pump(MVRHP)for treating such wastewater.Here,Aspen PlusTM as a powerful set of chemical process simulation software is utilized to investigate the economy and feasibility of the novel process.Comparison of the results of two process simulations,it can be seen that it is possible to reduce the total annual cost by nearly 45%to adopt the novel process,despite the capital investment increase 45%more than the conventional process.Thus,the provided conceptual design will play a guiding role in the industrialization of the process.

Effect of Packing Materials and Other Parameters on the Air Stripping Process for the Removal of Ammonia from the Wastewater of Natural Gas Fertilizer Factory

Air-stripping method was used to remove ammonia from the wastewater collected from natural gas fertilizer factory. Different materials were used as packing materials for the air stripping system. The effect of pH over 10.5, air-water flow ratio, nature of packing materials, height of materials and initial influent concentration of ammonia on air stripping unit were investigated. An attempt has been made to find out the stripping con-stant. Stripping constant was found to be .001, 0014, .001 and .0009 for coal, plastic ring, stone chips and wood chips, respectively. Best result was found for plastic ring for its higher surface area. Wood chips did not give good result, because the chips amalgamate with each other and hence reduces the surface area.

Study of Technology of Stripping Nickel Coating on NdFeB Permanent Magnet

The influences of category and density of reagents, temperature and the value of pH in the solution of stripping the nickel coating on NdFeB permanent magnet on the stripping result were studied systematically.The practical formular contains mainly the oxidant m-O2NC6H4SO3Na, the complex reagent ( NaOOCCH2 ) 2N( CH2 ) 2N( CH2COOH)2,the reagent of retarding corrosion KF and the calatyze RL-3 was obtained.

DYNAMIC ANALYSIS OF GAS STRIPPING DURING ETHANOL FERMENTATION IN CSTR

1 INTRODUCTIONInhibition phenomena have frequently been observed in microbial reactions.When thesubstrate concentration in the broth is high enough,the contour curve of the specificgrowth rate of cells is no longer monotonically increasing in a substrate-product phaseplane.The system exhibits a substrate inhibition.Some supersession products can affectthe growth and the yield of the cells as well as the viability of the microorganisms.Forexample,in the case of using Saccharomyces,the ethanol product inhibits the

Extraction and Stripping of Ytterbium (Ⅲ) from H_2SO_4 Medium by Cyanex 923

The extraction and stripping of ytterbium（ Ⅲ） from sulfuric acid medium using Cyanex 923 in heptane solution was investigated. The effects of extraetant concentration, pH and sulfate ion as well as stripping agents, acidity and temperature on the extraction and stripping were studied. The equilibrium constants and thermodynamic parameters, such as △n （10.76 kJ·mol^-1）, △G （-79.26 kJ·mol^-1） and △S （292.41 J·K^-1·mol^-1）, were calculated. The extraction mechanism and the complex species extracted were determined by slope analysis and FTIR spectra. Furthermore, it was found that the extraction of Yb （Ⅲ） from sulfuric acid medium by Cyanex 923 increased with pH, concentration of SO4^2-, HSO4^-, and extractant concentration, and approximately a quantitative extraction of Yb（ Ⅲ） was achieved at an equilibrium pH near 3.0, and the extracted complex was YbSO4（HSO4）·2Cyanex923（o）.

Combined Descemet stripping automated endothelial keratoplasty and intravitreal dexamethasone implant for concomitant pseudophakic bullous keratopathy and cystoid macular edema

Dear Editor,Endothelial cell density decreases with age and in various ocular conditions,including corneal endotheliitis,uveitis,pseudoexfoliation syndrome,and birth injury(1)The reduction of endothelial cell density is exacerbated over time after intraocular surgery(1)Descemet stripping automated endothelial keratoplasty(DSAEK)is considered the primary procedure for patients with only endothelial dysfunction.

Extraction and stripping kinetics of copper(Ⅱ)by N902 using single drop technique

The kinetics of extraction and stripping of copper （Ⅱ） was investigated by the single drop technique with a new extractant N902 （a derivative of the salicylal-doxime） and the rate equations of extraction and stripping were derived, respectively. The apparent activation energies of extraction and stripping were estimated to be 20.14 kJ/mol and 30.0 k J/mol.

Adsorptive Stripping Voltammetric Study of the Enhancement of Copper(Ⅱ) by Poly(vinyl alcohol), Starch and Polyallylamine

Adsorptive enhancements of several water-soluble polymers on copper(Ⅱ) were studied by adsorptive stripping voltammetry with a hanging mercury drop electrode. Increases in peak current of cu(Ⅱ) were observed in alkaline carbonate media. The enhancing power of poly(vinyl alcohol), starch and polyallylamine is 15, 4. 1, and 2.5 times, repectively

Clinical results of non-Descemet stripping endothelial keratoplasty

AIM： To investigate the impact of non-Descemet stripping endothelial keratoplasty（non-DSEK） on graft rejection rate,and its overall procedural effectiveness in patients.METHODS： Non-DSEK was performed on 65 eyes of 64 patients,and the procedural outcomes,including rejection episodes,failure and dislocation of the grafts,best corrected visual acuity（BCVA）,endothelial cell density（ECD）,and other complications,were analyzed retrospectively.RESULTS： Of the 65 eyes,63 recovered from bullous keratopathy with a clear cornea.The mean follow-up time was 26.4mo（range,6-84mo）.The mean BCVA improved from 1.70 log MAR preoperatively to 0.54 log MAR at 3mo,0.46 logM AR at 6mo,and 0.37 logM AR at 1y after surgery.The postoperative donor ECD of the 25 patients who successfully underwent specular microscopic examination was 1918±534 cells/mm^2（range,637 to 3056 cells/mm^2）,and the mean endothelial cell loss was 41.9% at 24 mo postoperatively.One eye developed secondary glaucoma and required regrafting via penetrating keratoplasty（PKP）.Another eye had postoperative graft failure due to rejection at 26 mo.Postoperative graft dislocation occurred in eight eyes.All of the eight dislocated grafts were reattached using air reinjection.CONCLUSION： Immunological graft rejection of the donor graft rarely occurs in non-DSEK.Therefore,non-DSEK is a safe,concise,and effective alternative to restore corneal decompensation when the Descemet membrane is disease-free.

Dynamic capacity balance between stripping and mining of a dragline stripping system

The reliability factors of a dragline stripping system were analyzed using system reliability theory to improve its reliability and ensure the stability of surface coal mine production.The relationship between the dragline scheduled stripping volume with both the weighted average thickness of the coal seam and the height of the blast casting bench was derived.The results show that the reliability of the dragline stripping system decreases with the weighted average thickness of the coal seam and increases with a reduced casting blast bench height and monthly raw coal production capacity.Furthermore,the dynamic monthly advance distance of the dragline stripping system was found,a new concept of the dragline stripping system reliability and measurement methodology were proposed,and a prediction model for the dragline production capacity was established using a generalized regression neural network.In addition,the steps and processes of the reliability were improved.The study on the Heidaigou surface mine shows that the height of the casting blast bench should be reduced to 10.5 m when its raw coal production capacity is improved from 20 to 30 Mt/a.During the normal production of surface coal,the system reliability can be improved by dynamically determining the weighted average coal seam thickness,accurately predicting the dragline production capacity,and taking other corresponding measures.

Dendrite‑Free and Stable Lithium Metal Battery Achieved by a Model of Stepwise Lithium Deposition and Stripping

The uncontrolled formation of lithium(Li)dendrites and the unnecessary consumption of electrolyte during the Li plating/stripping process have been major obstacles in developing safe and stable Li metal batteries.Herein,we report a cucumber-like lithiophilic composite skeleton(CLCS)fabricated through a facile oxidationimmersion-reduction method.The stepwise Li deposition and stripping,determined using in situ Raman spectra during the galvanostatic Li charging/discharging process,promote the formation of a dendrite-free Li metal anode.Furthermore,numerous pyridinic N,pyrrolic N,and CuxN sites with excellent lithiophilicity work synergistically to distribute Li ions and suppress the formation of Li dendrites.Owing to these advantages,cells based on CLCS exhibit a high Coulombic efficiency of 97.3%for 700 cycles and an improved lifespan of 2000 h for symmetric cells.The full cells assembled with LiFePO_(4)(LFP),SeS_(2) cathodes and CLCS@Li anodes demonstrate high capacities of 110.1 mAh g^(−1) after 600 cycles at 0.2 A g^(−1) in CLCS@Li|LFP and 491.8 mAh g^(−1) after 500 cycles at 1 A g^(−1) in CLCS@Li|SeS2.The unique design of CLCS may accelerate the application of Li metal anodes in commercial Li metal batteries.

The Effect of Atmospheric Plasma Paint Stripping on the Fatigue Crack Growth Properties of Aluminium Substrates

Paint removal is a common maintenance requirement for aircraft as well as naval and land vehicles, since external paint gets damaged and loses much of its corrosion protection effectiveness with time. Paint removal is also conducted when metallic aircraft structures are inspected periodically for fatigue cracks and corrosion. The conventional methods of removing paint employed throughout the Canadian Forces mainly include chemical stripping and abrasive media blasting. Chemical stripping involves the use of hazardous chemicals, which are high in Volatile Organic Compounds (VOC) and Hazardous Air Pollutants (HAP). Abrasive media blasting typically results in a substantial quantity of solid waste consisting of paint and blast residues. Such waste is subject to control under increasingly stringent environmental and safety regulations and its disposal is costly. The new Atmospheric Plasma (AP) paint removal process purports to be a high chemical energy, low thermal energy (cold plasma process), that should not damage temperature sensitive substructures, such as heat treated aerospace aluminium alloys. Fatigue strength is one of the key properties in aircraft structures. In order for AP paint stripping to be accepted as an aerospace industry standard paint removal process, it must be thoroughly tested to demonstrate that it does not adversely affect the fatigue properties of the substrate. This paper investigates effect of the paint removal process on fatigue crack growth of 7075-T6 and 2024-T3 aluminium panels.