1.25%碳酸氢钠雾化与温湿化治疗对气管切开患者气道功能的影响

比较1.25%碳酸氢钠雾化与温湿化治疗与常规气道湿化对气管切开患者的气道功能的临床疗效。方法 经皮气管切开人工气道且脱离机械通气24h的患者20例,根据接受的气道湿化方案的不同分为观察组和对照组。观察组和对照组各10例。对照组采用常规气道湿化治疗,观察组在常规湿化治疗上增加1.25%碳酸氢钠雾化联合持续主动加热湿化器治疗方法。比较两组痰液粘稠程度、气道口的温湿度、动脉血气指标。结果 观察组与对照组治疗前后对于气道口温度湿度的影响有显著差异性(P<0.05);在痰液黏稠度的影响上体现出显著差异性(P<0.05)。结论 1.25%碳酸氢钠雾化联合主动加热湿化器湿化方法相比于常规湿化方法能够有效保持气道吸入气体所需的温度湿度,有效改善痰液黏稠度和减少气道不良事件。

四种材料对釉质再矿化及脱矿抑制作用的体外研究

目的:体外评价奥威尔牙膏、绿茶浸提液、碳酸氢钠液、多乐氟对釉质的再矿化及脱矿抑制的作用。方法:(1)釉质再矿化实验:选择60个离体牙,用酸蚀剂脱矿30 s后,随机分为5组(n=12),分别使用人工唾液(A组)、奥威尔牙膏(B组)、绿茶浸提液(C组)、碳酸氢钠液(D组)、多乐氟(E组)处理12 d;(2)釉质脱矿抑制实验:另选择60个离体牙,不进行脱矿处理,随机分为5组(n=12),处理方法同釉质再矿化实验各组;12 d后将5组均置于可口可乐中脱矿3次,每次浸泡1 h,间隔12 h。两个实验均用SEM观察釉质表面形貌,能谱分析仪(EDS)分析釉质表面钙磷比。结果:(1)釉质再矿化实验:SEM观察结果显示,B、C、D、E组均有沉积物附着于釉质表面凹陷内;钙磷比值依次为C、D组> E组> B组> A组(P<0.05; C vs D,P> 0.05);(2)釉质脱矿抑制实验:SEM观察结果显示,A、B组釉质表面有明显凹陷,C、D、E组凹陷较浅,且有沉积物附着;钙磷比值依次为C组> D组> E组> A、B组(P<0.05; A vs B,P>0.05)。结论:奥威尔牙膏、绿茶浸提液、碳酸氢钠液、多乐氟均有再矿化能力和抑制釉质脱矿作用,其中绿茶浸提液和碳酸氢钠液的效果优于多乐氟和奥威尔牙膏。

Thermodynamic simulation of stepwise precipitation of NH_(4)VO_(3)and NaHCO_(3)from carbonating Na_(3)VO_(4)solution

Thermodynamic simulation was conducted to design a new process of stepwise precipitating NH_(4)VO_(3)and NaHCO_(3)from regulating the CO_(2)carbonation of Na_(3)VO_(4)solution.Firstly,a new V(V)speciation model for the aqueous solution containing vanadate and carbonate is established by using the Bromley-Zemaitis activity coefficient model.Subsequently,thermodynamic equilibrium calculations are conducted to clarify the behavior of vanadium,carbon,sodium,and impurity species in atmospheric or high-pressure carbonation.To ensure the purity and recovery of vanadium products,Na_(3)VO_(4)solution is initially carbonated to the pH of 9.3-9.4,followed by precipitating NH_(4)VO_(3)by adding(NH_(4))_(2)CO_(3).After vanadium precipitation,the solution is deeply carbonated to the final pH of 7.3-7.5 to precipitate NaHCO_(3),and the remaining solution is recycled to dissolve Na_(3)VO_(4)crystals.Finally,verification experiments demonstrate that 99.1%of vanadium and 91.4%of sodium in the solution are recovered in the form of NH_(4)VO_(3)and NaHCO_(3),respectively.

Synergistic degradation of phenols by bimetallic CuO-Co_3O_4@γ-Al_2O_3 catalyst in H_2O_2/HCO_3^- system

The development of new catalytic techniques for wastewater treatment has long attracted much attention from industrial and academic communities.However,because of catalyst leaching during degradation,catalysts can be short lived,and therefore expensive,and unsuitable for use in wastewater treatment.In this work,we developed a bimetallic CuO-Co3O4@γ-Al2O3 catalyst for phenol degradation with bicarbonate-activated H2O2.The weakly basic environment provided by the bicarbonate buffer greatly suppresses leaching of active Cu and Co metal ions from the catalyst.X-ray diffraction and X-ray photoelectron spectroscopy results showed interactions between Cu and Co ions in the CuO-Co3O4@γ-Al2O3 catalyst,and these improve the catalytic activity in phenol degradation.Mechanistic studies using different radical scavengers showed that superoxide and hydroxyl radicals both played significant roles in phenol degradation,whereas singlet oxygen was less important.

Bicarbonate activation of hydrogen peroxide: A new emerging technology for wastewater treatment

The serious limitations of available technologies for decontamination of wastewater have compelled researchers to search for alternative solutions. Catalytic treatment with hydrogen peroxide, which appears to be one of the most efficient treatment systems, is able to degrade various organics with the help of powerful ·OH radicals. This review focuses on recent progress in the use of bicarbonate activated hydrogen peroxide for wastewater treatment. The introduction of bicarbonate to pollutant treatment has led to appreciable improvements, not only in process efficiency, but also in process stability. This review describes in detail the applications of this process in homogeneous and heterogeneous systems. The enhanced degradation, limited or lack of leaching during heterogeneous degradation, and prolonged catalysts stability during degradation are salient features of this system. This review provides readers with new knowledge regarding bicarbonate, including the fact that it does not always harm pollutant degradation, and can significantly benefit degradation under some conditions.

Electrolytic Regeneration of Decarbonising Potassium Carbonate Solution

In this work,the regeneration mechanism of potassium carbonate solution after absorption of CO2 using ion-exchange membrane electrolysis was presented.The solutions of potassium carbonate(K2CO3) and potassium bicarbonate(KHCO3) were used to simulate the solution after absorbing CO2.Experiments were carried out at various electrodes,temperatures and current densities.The results indicate that the membrane electrolysis can in-crease concentration ratio of K2CO3 and KHCO3,and achieve 100%conversion.In this process,not only CO2 is desorbed from carbonate solution,but also hydrogen,as a byproduct,is generated at the cathode,which is the main contributor to reduce energy consumption.Thus,the membrane electrolysis is valuable in the regeneration of the K2CO3 absorbent.

Catalytic synthesis of diethyl carbonate with supported Pd-Cu bimetallic nanoparticle catalysts:Cu(Ⅰ) as the active species

Cupric oxide （CuO） and copper-cuprous oxide （Cu-Cu2O） nanoparticles were prepared by a simple hydrothermal method for the synthesis of diethyi carbonate （DEC） from ethanol. During these syntheses, varying NaOH and glucose concentrations were applied to explore and pinpoint the active species. It was found that PdCl2/CuO and PdCI2/Cu-Cu2O both catalysts exhibited good thermal stability and morphology. The results of catalytic tests showed that the catalysts prepared with 5 mol/L NaOH show superior catalytic performances because of their lower extent of agglomeration. It is noteworthy that the PdC12/Cu-Cu2O catalysts were the most active, especially the PdCl2/Cu-Cu2O catalyst prepared with 10 mmol glucose and having a higher Cu2O concentration. In Pd（ll）-Cu（II） （PdCl2/CuO） catalysts, there is an induction period, during which Pd（II） is reduced to Pd（0）, that must occur prior to electron transfer between Pd and Cu, and this can slow the catalytic reaction. To further pinpoint the active species, PdCl2/Cu-Cu2O catalysts with different Cu2O contents were prepared by controlling the dosages of glucose. The maximum DEC yield obtained with these catalysts was 151.9 mg.g-1.h-1, corresponding to an ethanol conversion of 7.2% and 97.9% DEC selectivity on an ethanol basis. Therefore, it was concluded that Cu＋ was the active species in this catalytic system, possibly because a higher proportion of Cu＋ reduces the Pd2＋ concentration and limits the CO oxidation side reaction, thus increasing DEC selectivity. In addition, Cu＋ promotes electron transfer between Pd and Cu without an induction period, which could also promote the catalytic activity.

Synthesis of Bisphenols Carrying Long Hydrocarbon Side Chains

Bisphenols containing long aliphatic hydrocarbon side chains were synthesized by the condensation of phenol with aldehyde or ketone in the presence of heteropolyacid. Their structures were characterized by IR, 1H NMR, 13C NMR and element analysis. The experiment results show that when heteropolyacid was used as a catalyst, these bisphenols were obtained in high selectivity and high yields.

Physical-Chemical Aggressiveness of Solutions of Medicines as a Factor in the Rheology of the Blood inside Veins and Catheters

In experiments in vitro and observations in the clinic in vivo studied the state of the lumen of subcutaneous veins and blood rheology of patients after their interaction with vascular catheters and solutions of medicines based on the values of temperature, volume, concentration, osmotic activity and pH. It is shown that heparin injection in blood not prevent, but solution of 4% sodium bicarbonate injection prevents blood clotting, blood clots and blockage blood clots of veins and of catheters. It is shown that the heating to a temperature of＋42 ℃ with the solution of 4% sodium bicarbonate provides softening action on old dry blood clots in 1 min, and their subsequent irrigation with a warm solution of 4% sodium bicarbonate and 3% hydrogen peroxide provides complete destruction and discoloration of the remaining spots of blood during 2 s. Proposed new medicines and hygiene products for the protection of the veins and installed in them vascular catheters from blockage of blood clots, and for removing blood stains from clothes and body surface patients.

碱压煮法生产电池级碳酸锂

电池级碳酸锂是锂电池的关键材料,目前锂辉石硫酸法工艺是主要制备途径,该方法存在酸雾污染环境、设备腐蚀和产品质量不稳定等问题。与硫酸法工艺对比,碱压煮法生产碳酸锂工艺具有生产流程短、环保效果好、锂回收率高和加工成本低等优点,成为当前行业关注的热点技术。本文结合中国恩菲工程技术有限公司的生产实践和锂盐行业的研究成果,系统阐述了碱压煮法生产电池级碳酸锂的反应机制和最佳工艺流程,并重点探讨了转型焙烧、碱压煮和碳酸氢化-热析等关键工序的影响因素。进一步明确了其最佳控制条件是:转型焙烧工序温度1000~1150℃;碱压煮工序碱比1.9~2.1,反应温度235℃,反应时间1 h;碳酸氢化-热析工序碳酸氢化温度小于40℃,热解温度大于90℃,一次碳酸氢化用液固比30∶1~40∶1,二次碳酸氢化液固比20∶1~25∶1。以此推动碱压煮法生产电池级碳酸锂集成技术的系统研究和成功开发,为锂盐产业绿色高效发展提供新的思路和解决方案。

Efficient hydrocarboxylation of alkynes based on carbodiimide‐regulated in situ CO generation from HCOOH:An alternative indirect utilization of CO_(2)

The role of carbodiimide as dehydrant in the chemo‐,regio‐and stereoselective Pd(Ⅱ/0)‐catalyzed hydrocarboxylation of various alkynes with HCOOH releasing CO in situ is reported for the first time to obtainα,β‐unsaturated carboxylic acids.Both symmetrical and unsymmetrical monoalkynes show good reactivity.Importantly,2,2’‐(1,4‐phenylene)diacrylic acid can also be synthesized in high yield through the dihydrocarboxylation of 1,4‐diethynylbenzene.Besides,an excellent result in gram scale experiment and TON up to 900 can be obtained,displaying the efficiency of this protocol.Notably,regulating the types and concentrations of dehydrant can control the CO generation,avoiding directly operating toxic CO and circumventing sensitivity issue to the CO amount.On the basis of the attractive features of formic acid including easy preparation through CO_(2) hydrogenation and efficient liberation of CO,this protocol using formic acid as bridging reagent between CO_(2) and CO can be perceived as an indirect utilization of CO_(2),offering an alternative method for preparing acrylic acid analogues.

A novel strategy for immobilization of thionine based on calcium carbonate-gold nanoparticles inorganic hybrid composite and its application in hydrogen peroxide sensor

A novel strategy for efficient immobilization of electroactive Thionine(Th)on the gold(Au)electrode surface based on calcium carbonate-gold nanoparticles(CaCO3-AuNPs)inorganic hybrid composite was proposed and conducted by the strong electrostatic interaction between positively charged Th and negatively charged CaCO3-AuNPs composite.The hybrid composite was obtained by the adsorption of AuNPs onto the surface of CaCO3 microspheres through electrostatic interaction.Due to the microporous architecture,large surface area,and good biocompatibility of CaCO3-AuNPs composite,the amount and stability of the immobilized Th were highly strengthened.The application of the resulting Th modified electrode in the hydrogen peroxide(H2O2)sensor was also investigated.It exhibited rapid response to H2O2 within 3 s.The linear calibration ranged from 8.00×107to 1.06×10 -3mol/L with a detection limit of 2.00×10 -7mol/L.

Hydrocarbon charging of the Ordovician reservoirs in Tahe-Lunnan area, China

The Tahe-Lunnan hydrocarbon province is China's largest region with oil-and-gas-producing marine carbonate rocks. However, in terms of multi-source hydrocarbon generation, multi-episode reservoir adjustment and reconstruction, it remains unsettled how to determine the geological period of primary hydrocarbon filling of the Ordovician reservoir in this region. Based on the analysis of distribution and properties of reservoir, hydrocarbon filling of the Cambrian source rocks in the Late Caledon stage has largely been destroyed. However, hydrocarbon filling of the Middle Ordovician source rocks in the Early Carboniferous resulted in the major body of crude oil. During the charging process, the hydrocarbons were oxidatively degraded to heavy oil due to the poor closure conditions, which is corroborated by homogenization temperature of inclusions. Moreover, the capturing of hydrocarbon inclusions with high-temperature does not represent the filling of mature petroleum in the later period, but represents the result of the natural gas containing light fraction. Therefore, the Tahe-Lunnan area underwent two hydrocarbon filling processes, and the invasion of excessive dry gas led to a gas-washing fractionation upon the original Ordovician reservoirs.

HCl Dry Removal with Modified Ca-Based Sorbents at Moderate to High Temperatures

Modified Ca-based sorbents were obtained by adding sodium alkali into Ca(OH)2 and CaCO3. Reactive properties of modified Ca-based sorbents with acidic gases were investigated through reacting with gaseous HC1 at 450-760℃, and SEM and XRD technologies were adopted to get information on the reaction mechanism. Experimental data showed that HC1 dry removal efficiencies increased with temperature before 700℃ for all of the investigated sorbents, and there existed improved sorbents that corresponded to the highest removal efficiencies under the similar conditions. SEM photographs exhibited morphology difference between original and improved sorbents both before and after the reaction; and displayed that improved sorbents formed more porous product layers than original sorbents especially at higher temperature when product sintering became heavier, which is favorable to HC1 dry removal. XRD analysis showed that (1) improved Ca(OH)2 and CaCO3 were less crystalline than original lime and limestone; (2) the reaction product species of improved Ca(OH)2 changed with reaction temperature, while for original Ca(OH)2 the same product species appeared for all of the tested temperatures; and (3) for improved CaCO3, the only product at lower temperatures was CaCl2.2H2O and more product species were produced when temperature was higher than 650℃, but no CaCl2.Ca(OH)2.H2O formed at 700℃, while for the case of original CaCO3, the undesired CaCl2.Ca(OH)2.H2O appeared at 700℃. Presently, reaction temperature interval of 650-700℃ is recommended for improved Ca(OH2) to get the highest efficiency, for improved CaCO3 reaction at higher temperature deserves further investigation to make a good choice.

Microcapsules with compact wall from hydrocarbon/fluorocarbon composite surfactants for electrophoretic display

The components and their concentration ratio of surfactant mixture in aqueous solution of gelatin and sodium carboxymethylcellulose (NaCMC) are very important during the preparation of stable microcapsules for electrophoretic display.In this work,hydrocarbon/fluorocarbon composite surfactant was introduced for the first time into the capsule wall to improve the chemical resistance and barrier property of the microcapsules.By investigating surface tension and zeta potential of NaCMC with the mixture of sodium dodecyl sulfate (SDS)/perfluoro-nonene oxy benzene sulfonate (OBS),we found that both the presence of hydrophobic interaction and the hydrogen bonding between NaCMC and SDS/OBS enhanced the adsorption of NaCMC at the oil/water interface and thus facilitated the formation of capsule wall.The morphology,particle size,surface free energy and thermal stability of the obtained microcapsules were characterized.The results showed that optically transparent microcapsules with uniform size,smooth surface and compact wall can be obtained by adjusting the pH value of the reaction system and the concentration ratio of SDS/OBS.Based on the prepared microcapsules,a matrix display prototype operated at 9 V direct current in static driven mode was fabricated.