Plasma activation towards oxidized nanocarbons for efficient electrochemical synthesis of hydrogen peroxide

Oxidized nanocarbons(ONCs)have been regarded as efficient electrocatalysts for H2O2 production.However,wet chemical procedures involving large volumes of strong acid and long synthetic time are usually needed to obtain these ONCs.Herein,a plasma activation strategy is developed as a rapid and environmentally benign approach to obtain various ONCs,including oxidized multiwalled carbon nanotubes,single-walled carbon nanotube,graphene,and super P carbon black.After a few minutes of plasma activation,oxygen-containing functional groups and defects can be effectively introduced onto the surface of nanocarbons.Enhanced electrocatalytic activity and selectivity are demonstrated by the plasma-ONCs for H2O2 production.Taking oxidized multiwalled carbon nanotubes as an example,high selectivity(up to 95%)and activity(0.75 V at 1 mA cm^(−2))can be achieved in alkaline solution.Moreover,ex situ x-ray photoelectron spectroscopy and in situ Raman measurements reveal that C–O,C=O,edge defect,and sp2 basal planar defect are probably the active sites.

Plasma Activation of Integrated Carbon Nanotube Electrodes for Electrochemical Detection of Catechol

In this study, integrated multi-wall carbon nanotube （MWCNT） electrodes were prepared in the holes of glass directly by microwave plasma chemical vapour deposition （MWPCVD）. The electrochemical behaviour of catechol at the integrated MWCNT electrodes was investigated. The oxygen plasma treated CNT electrodes had better electrochemical performance for the analysis of catechol than that of as-synthesized CNT electrodes. Both the as-synthesized CNTs and plasma treated CNTs were characterized by TEM（transmission electron microscopy, XPS（X-ray photoelectron spectroscopy） and Raman spectroscopy. The results revealed that the oxygen plasma activation is an effective method to enhance the electrochemical properties of CNT electrodes.

Partial Oxidation of Methane with Sol-Gel Fe/Hf/YSZ Catalyst in Dielectric Barrier Discharge: Catalyst Activation by Plasma

A 1% Fe-30% Hf over yttria-stabilized zirconia catalyst in combination with novel plasma-assisted activation techniques for a direct partial oxidation of methane to methanol was tested using dielectric barrier discharge plasma at ambient temperature and atmospheric pressure. However, instead of methanol, the reaction products were dominated by HE, CO, CO2, C2, and H2O. A catalytically activated plasma process increased the production of methanol compared with a noncatalytic plasma process. The maximum selectivity of methanol production was achieved using a catalyst that was treated at higher applied power.

Effect of different process conditions on the physicochemical and antimicrobial properties of plasma-activated water

The physicochemical properties of plasma-activated water(PAW)generated under different process conditions were investigated,and their changes under different storage conditions were also studied.The results showed that increasing the processing time and power,and decreasing generated water volume,could cause an increase in the redox potential,conductivity,and temperature of PAW,and a decrease in its pH.A slower dissipation of the reactive oxygen and nitrogen species in PAW was found on storage at 4℃in a sealed conical flask than on storage at room temperature.The inactivation ability of plasma-activated lactic acid(LA)to Listeria monocytogenes(L.monocytogenes)and Pseudomonas aeruginosa(P.aeruginosa)was higher than that of PAW or LA alone under the same experimental conditions.The results of this study may provide theoretical information for the application of PAW as a potential antimicrobial agent in the future.

Rice plant growth and yield: foliar application of plasma activated water

Plasma activated water(PAW)was prepared for 10 min to be applied one tofive times as a foliar spray to rice plants,to investigate plant growth,yield and the concentrations of total soluble protein and sugar in the rice grains produced.The results reveal that(1)the plant height,stem diameter,dry weight,chlorophyll and total carotene concentrations were improved by∼15%,∼25%,∼24%,∼47%and∼45%,respectively,with respect to control,(2)defense mechanisms of the plants treated with PAW were improved,(3)concentrations of total soluble protein and sugar were enhanced in the rice grains of PAW treated plants and(4)yield was increased by∼14%.

Microstructure and Mechanical Performance of Cu-SnO_2-rGO based Composites Prepared by Plasma Activated Sintering

A novel chemical technique combined with unique plasma activated sintering（PAS） was utilized to prepare consolidated copper matrix composites（CMCs） by adding Cu-SnO2-rGO layered micro powders as reinforced fillers into Cu matrix. The repeating Cu-SnO2-rGO structure was composed of inner dispersed reduced graphene oxide（r GO）, SnO2 as intermedia and outer Cu coating. SnO2 was introduced to the surface of rGO sheets in order to prevent the graphene aggregation with SnO2 serving as spacer and to provide enough active sites for subsequent Cu deposition. This process can guarantee rGO sheets to suffi ciently disperse and Cu nanoparticles to tightly and uniformly anchor on each layer of rGO by means of the SnO2 active sites as well as strictly control the reduction speed of Cu^2＋. The complete cover of Cu nanoparticles on rGO sheets thoroughly avoids direct contact among rGO layers. Hence, the repeating structure can simultaneously solve the wettability problem between rGO and Cu matrix as well as improve the bonding strength between rGO and Cu matrix at the well-bonded Cu-SnO2-rGO interface. The isolated rGO can effectively hinder the glide of dislocation at Cu-rGO interface and support the applied loads. Finally, the compressive strength of CMCs was enhanced when the strengthening effi ciency reached up to 41.

Sawtooth Activity in Ohmically Heated Plasma on HT-7 Tokamak

Sawtooth activity on HT-7 tokamak has been investigated experimentally mainly by using soft x-ray diode array and magnetic probes. Their behaviors and occurrences are correlated closely to the discharge conditions: the electron density Ne, the electron temperature Te, the safety factor qa on plasma boundary and wall condition etc. When central line-averaged electron density Ne(0) is over 2.0×1013cm-3 , major sawtooth activity emerges with a period of up to 6.5 ms and a fluctuation amplitude of up to 2-30 % of SXR radiation signal. In some cases such as the safety factor between 4.2-4.7 and Zeff=3.0-6.0, a monster sawtooth activity often emerges without apparent deterioration of plasma confinement and without major disruption. During these events, abundant MHD phenomena are observed including partial sawtooth oscillations. In this paper, the observed sawtooth behaviors and their dependence on the and their dependence density Ne and wall condition in ohmically heated plasma are introduced, the results are discussed and presented.

Molecular mechanism study of Astragalus adsurgens Pall synergistically induced by plasma and plasma-activated water

The mutagenic effects of discharge plasma and plasma+PAW(plasma and its activated water combined) on Astragalus adsurgens Pall seeds were explored. Needle array-plate dielectric-barrier discharge plasma was used to treat A. adsurgens Pall seeds and PAW was prepared at the same time.The deionized water and the obtained PAW were used to cultivate plasma-treated seeds in groups and the survival rate of each group was counted. Results showed that the survival rate of the treated seeds of A. adsurgens Pall when cultured with deionized water was not significantly different from that of the control check(CK). The culture with PAW had an obvious lethal effect and each group reached the half-lethal dose. Reactive oxygen species(ROS) and RNA-Seq analysis of seedlings in the 3 h treatment group showed that the content of ROS in the 3 d post-treatment group was significantly higher than that of the CK. Because expression of the gene with the function of scavenging superoxide free radicals was upregulated, the ROS content of seedlings on the sixth day was significantly lower than that on the third day. Plasma and plasma+PAW treatments changed a large number of gene expressions;particularly, the plasma+PAW group caused plant-growth genes to be significantly upregulated. After treatment, the seedlings of A. adsurgens Pall may grow faster and have higher nutritional value. This research is of great significance to the wider application of isoelectronic bodies and their activated water physicochemical mutagens in biological effects and breeding research.

Plasma activated water prepared by different plasma sources:physicochemical properties and decontamination effect on lentils sprouts

The pulsed corona discharge(CD)generated in contact with water and directly in water,and high-power air plasma jet(APJ)were studied for production of plasma activated water(PAW).The changes of physical(pH,redox potential,conductivity,temperature)and chemical(peroxides,nitrites,nitrates concentrations)properties of treated water were investigated.The comparison of CD generated in gas/water interface and underwater configuration in the same system showed that the interaction of reactive oxygen and nitrogen species formed in ambient air in gas/water system induces different chemical processes,leading to lower pH,higher oxidation-reduction potential(ORP)and higher conductivity of PAW than in underwater discharge.High yield of peroxide was observed in both configurations.The PAW prepared by APJ exhibits high concentration of nitrites and nitrates according to supplied energy,and related significant decrease of pH and increase of ORP and conductivity after treatment.The antimicrobial effect of PAW prepared by CD and plasma jet on lentils sprouts was studied in different treatment and washing times.The APJ appears to have great efficacy on water activation resulted in strong decontamination effect.The PAW treated by APJ for 10 min led to bacterial reduction from initial 8.3 to 5.9 and 4.0 log10 CFU g^(-1)after 10 and 30 min of washing,respectively.

Effect of Different Proportions of Leymus chinensis in Diet on Plasma Enzymes Activities of Wulong Geese

Eight-month-old Wulong geese were fed with the diet with different proportions of Leymus chiesensis at the same energy and protein level. The activities of plasma Alkaline Phosphatase （AKP）, Acid Phosphatase （ACP）, Choline Esterace （CHE）, Lactic Dehydrogenase （LDH）, Glutamicoxalacetic Transaminase （GOT） and Glutamatepyruvate Transaminase （GPT） were determined and then their correlations with fiber digestibility and the apparent digestibility of Ca, R Met and Cys were analyzed. The results showed that the activity of AKP took on a significant downtrend as the increasing of Leymus chinensis proportion （P〈0.05）. There was a negative correlation between the AKP activity and the digestibility of crude fiber （CF）, neutral detergent fiber （NDF） and acid detergent fiber （ADF） （P〈0.05）. However, there was a significant positive correlation between the AKP activity and the apparent digestibility of Ca, Met and Cys （P〈0.05）. Moreover, the activities of the other five enzymes had no significant correlation with the digestibility of CF, NDF, ADF, and the apparent digestibility of Ca, Met and Cys （P〉0.05）.

Monster Sawtooth Activity in Ohmically Heated HT-7 Plasma

Experimental properties of monster sawtooth activities in ohmic HT-7 plasma are presented in this paper. The monster sawtooth activities belong to global fluctuations and are characterized with a series of large core collapses on SXR intensity traces with a long period, a large amplitude fluctuation and a large inversion radius. However, they emerge without apparent deterioration of plasma confinement and without major plasma disruption. During the events, long partial sawtooth collapses and abundant MHD phenomena are also observed.

Effect of actuating frequency on plasma assisted detonation initiation

Aiming at studying the influence of actuating frequency on plasma assisted detonation initiation by alternating current dielectric barrier discharge, a loosely coupled method is used to simulate the detonation initiation process of a hydrogenoxygen mixture in a detonation tube at different actuating frequencies. Both the discharge products and the detonation forming process which is assisted by the plasma are analyzed. It is found that the patterns of the temporal and spatial distributions of discharge products in one cycle are not changed by the actuating frequency. However, the concentration of every species decreases as the actuating frequency rises, and atom O is the most sensitive to this variation, which is related to the decrease of discharge power. With respect to the reaction flow of the detonation tube, the deflagration-todetonation transition（DDT） time and distance both increase as the actuating frequency rises, but the degree of effect on DDT development during flow field evolution is erratic. Generally, the actuating frequency affects none of the amplitude value of the pressure, temperature, species concentration of the flow field, and the combustion degree within the reaction zone.

Improvement of AlN Thermal Conductivity Based on Reductive Compound Additives

AlN ceramics were prepared by plasma activation sintering(PAS)with compound additives yttrium acetylacetonate(Y(acac)_(3))and melamine(C_(3)H_(6)N_(6)).The effects of compound additives on the microstructure,density,and thermal properties of Al N ceramic were studied.Y(acac)3and C_(3)H_(6)N_(6)can form Y_(2)O_(3),residual organic carbon and reducing gas during the heating process,which improves the Al N sintering performance at a temperature of 1700℃and the bulk thermal conductivity.When the content of Y(acac)_(3)is 10 wt%and C_(3)H_(6)N_(6)is 3 wt%,the thermal conductivity of Al N ceramics is 105.6 W/(m·K),which is much higher than that of Al N ceramics with Y_(2)O_(3)under the same sintering conditions.This work provides theoretical reference for the preparation of high-performance Al N ceramic.

Clinical Study on Zhuyu Tongfu (逐瘀通腑) Serial Recipe Combined with Acupuncture and Massotherapy in Treating Hypertensive Cerebral Hemorrhage

Objective. To observe the clinical efficacy and mechanism of Zhuyu Tongfu （逐瘀通腑, ZYTF） Serial Recipe combined with acupuncture and massotherapy in treating hypertensive cerebral hemorrhage （HCH）. Methods： One hundred and eighteen patients with hypertensive cerebral hemorrhage, on the basis of conventional Western medicine treatment, were randomly divided into ZYTF combined with acupuncture and massotherapy group （treated group） and simple Western medicine group （control group） ; the clinical efficacy, neurofunction deficit scoring （NDS） alterations and hematoma absorption rate of both groups were observed, and also the plasma superoxide dismutase （SOD） activity, plasma lipid peroxidase （LPO） content, erythrocyte glutathion peroxidase （GSH-Px） activity, hematocrit （Ht） and the whole blood viscosity （Va） change were also observed. Results： In the treated group, the clinical efficacy, NDS improvement and hematoma absorption rate were superior to that of the control group; comparison between the two groups after treatment showed that plasma SOD activity and GSH-Px activity got more elevated and plasma LPO content, Ht and Va more lowered in the the treated group than those in the control group. Cenclusien： ZYTF combined with acupuncture and massotherapy has better effect, its therapeutic mechanism was possibly correlated to the elevation of plasma SOD activity, GSH-Px activity and lowering of plasma LPO content, Ht and Va.

New developments for vacuum coating of steel strips

Vapor deposited coatings onto strip steel are a promising alternative as functional layers for corrosion protection or high abrasion resistance.Conventional coating systems have some limits regarding environmental compatibility,the range of coating materials and application properties. Physical vapor deposition(PVD) is an environment-friendly technology and enables nearly unlimited material and process variety.Electron beam high-rate evaporation with deposition rates up to some micrometers per second is the most productive PVD technology for low cost coating.The combination of evaporation with powerful plasma is an efficient way to improve the layer properties.The developed plasma sources can be used for special plasma enhanced chemical vapor deposition(PECVD) processes too. The paper gives an overview about the latest developments in these technologies.Furthermore,the paper explains some examples of new layer stacks onto steel strips.While enhanced corrosion protection can be obtained by magnesium,aluminium or copper containing coatings other functional surface properties come more and more in the focus of interest.For instance,decorative gold colored layers,transparent scratch resistant layers,hard coatings and photo catalytic layers were deposited on running steel strips.Functional layers and layer systems for energy saving and sun energy absorption by solar thermal effects and photo voltaics are under development.The coatings are prepared under the conditions of very high deposition rates using our in-line vacuum coater for metallic strips and sheets with the name MAXI.The influence of the process and plasma parameters on the layer properties were investigated and will be demonstrated for some applications.

The effects of long-term low-dose hormone replacement therapy on blood pressure and vasoactive factors in postmenopausal women

Objective:To investigate the effects of long-term low-dose hormone replacement therapy(HRT)on blood pressure,the plasma renin activity(PRA),plasma angiotensin Ⅱ(AngⅡ)leveland serum nitric oxide(NO)concentration in postmenopausal women.Methods:A total of 140 postmenopausal women were selected from the medical staff of thePeking Union Medical College Hospital.Of these,63 subjects who had been treated with low-dose sex hormone for over 5(5-32)years were set up as HRT group,and 77 age-matched sub-jects who had never received HRT were designed as control group.The levels of serum estradiol(E_2),follicle stimulating hormone(FSH)and nitric oxide(NO),the concentration of plasma an-giotensin Ⅱ(AngⅡ),plasma rennin activity(PRA)and the blood pressure were evaluated inthese two groups.Results:The serum level of estradiol in HRT group was significantly higher than that in con-trol group(median,interquartile range;124.0 pmol/L,113.4 vs.78.2 pmol/L,121.8)(P<0.05)and systolic blood pressure in HRT groups was significantly lower than that in control group[(126.7±14.4)mmHg vs.(132.4+19.8)mmHg](P<0.05).Diastolic blood pressure[(79.7±7.9)mmHg vs.(79.6±10.4)mmHg],the serum level of FSH[(54.4±18.9)IU/L vs.(60.4±24.4)IU/L],the plasma level of PRA(median,interquartile range;0.14 pg/L/hr,0.11vs.0.12 pg/L/hr,0.10),AngⅡ(median,interquartile range;46.0,31.1 pg/ml vs.44.4,33.0pg/ml)and serum level of NO(median,interquartile range;63.8 μmol/L,58.9 vs.56.0 μmol/L,94.8)showed no significant difference between HRT and control groups(P>0.05).Conclusions:Long-term low-dose HRT decreased the systolic blood pressure,but showed noeffects on the diastolic blood pressure,plasma level of AngⅡ,PRA,and serum level of NO inpostmenopausal women.

Effects of Zaizhang－Ⅰ，a Traditional Chinese Medicine，on Immunologically Mediated Aplastic Anemia in Mice

Immunologically mediated aplastic anemia in mice were used as animal models to study the the curative effect of Zaizhang-Ⅰin term of the changes of two pathogenetic aspects in aplastic mice,namely the defciency of hematopoietic stem cells and the disturbance of immunology. Our results demonstrated that in aplastic mice, after treatment by Zaizhang-Ⅰ,the loss of mature hematopoietice cells (WBC, RBC, Plt) were reduced, and marrow cellular cytosis,and their clinical findings were improved, indicating a partial remission. The present data show that its curative mechanism lies in the action of promoting the recovery of colony forming unit-spleen (CFU-S) and reversing immunologically-induced plasma colony forming unit granulocyte/macrophage (CFU-GM ) inhibitory activity. Natural killer cells activity (Nka) and interleukin-2 tumor necrosis factors (TNF) were also examined to further understand the mechanism by which Zaizhang-Ⅰreverse plasma hematopoietic activity.

EFFECTS OF CYPROHEPTADINE ON PLASMA SUPEROXIDE DISMUTASE ACTIVITY AND MALONDIALDEHYDE CONTENT IN RABBITS WITH HEMORRHAGIC SHOCK

Profound hemorrhagic shock was produced in thirty rabbits by exsanguination via the carotid artery until blood pressure (BP) reached 5.3 kPa (40 mmHg) and was sustained for a period of 90 minutes. The rabbits were equally divided into cyproheptadine (Cyp) treated group and control group. Blood samples 30 minutes after liquid and blood infusion and administration of Cyp (10 mg / kg) were collected from the carotid artery, and the plasma superoxide dismutase (SOD) activity and malondialdehyde (MDA) content measured. The results showed that Cyp remarkebly enhanced the plasma SOD activity (2462 338 vs 1955- 596, P<0.01) and reduced MDA content (2.68- 0.24 vs 3.20-0.49, P<0.01). We believe that the in crease of O2 production plays an important role in the develop-ment of shock, the single blood and liquid infusion can not significantly improve the shock conditions. Scavenging oxygen free radicals and alleviating cellular damage and multiple or gan failure are the possible mechanisms of cyproheptadine anti-shock effect.

Diagnostic value of aldosterone to renin ratio calculated by plasma renin activity or plasma renin concentration in primary aldosteronism: a meta-analysis

Background:Since the diagnostic value of aldosterone to renin ratio(ARR)calculated by plasma renin concentration(PRC)or plasma renin activity(PRA)is still inconclusive,we conducted a meta-analysis by systematically reviewing relevant literature to explore the difference in the diagnostic efficacy of ARR calculated by PRC or PRA,so as to provide guidance for clinical diagnosis.Methods:We searched PubMed,Embase,and Cochrane Library from the establishment of the database to March 2021.We included studies that report the true positive,false positive,true negative,and false negative values for the diagnosis of primary aldosteronism,and we excluded duplicate publications,research without full text,incomplete information,or inability to conduct data extraction,animal experiments,reviews,and systematic reviews.STATA 15.1 was used to analyze the data.Results:The pooled results showed that ARR(plasma aldosterone concentration[PAC]/PRC)had a sensitivity of 0.82(95%confidence interval[CI]:0.78-0.86),a specificity of 0.94(95%CI:0.92-0.95),a positive-likelihood ratio(LR)of 12.77(95%CI:7.04-23.73),a negative LR of 0.11(95%CI:0.07-0.17),and symmetric area under the curve(SAUC)of 0.982,respectively.Furthermore,the diagnostic odds ratio(DOR)of ARR(PAC/PRC)was 180.21.Additionally,the pooled results showed that ARR(PAC/PRA)had a sensitivity of 0.91(95%CI:0.86-0.95),a specificity of 0.91(95%CI:0.90-0.93),a positive LR of 7.30(95%CI:2.99-17.99),a negative LR of 0.10(95%CI:0.04-0.26),and SAUC of 0.976,respectively.The DOR of ARR(PAC/PRA)was 155.52.Additionally,we conducted a subgroup analysis for the different thresholds(<35 or≥35)of PAC/PRC.The results showed that the DOR of the cut-off≥35 groups was higher than the cut-off<35 groups(DOR=340.15,95%CI:38.32-3019.66;DOR=116.40,95%CI=23.28-581.92).Conclusions:The research results suggest that the determination of ARR(PAC/PRC)and ARR(PAC/PRA)was all effective screening tools for PA.The diagnostic accuracy and diagnostic value of ARR(PAC/PRC)are higher than ARR(PAC/PRA).In addition,within a certain range,the higher the threshold,the better the diagnostic value.

Review of low-temperature plasma nitrogen fixation technology

Nitrogen fixation is essential for all forms of life,as nitrogen is required to biosynthesize fundamental building blocks of creatures,plants,and other life forms.As the main method of artificial nitrogen fixation,Haber–Bosch process(ammonia synthesis)has been supporting the agriculture and chemical industries since the 1910s.However,the disadvantages inherent to the Haber–Bosch process,such as high energy consumption and high emissions,cannot be ignored.Therefore,developing a green nitrogen fixation process has always been a research hotspot.Among the various technologies,plasma-assisted nitrogen fixation technology is very promising due to its small scale,mild reaction conditions,and flexible parameters.In the present work,the basic principles of plasma nitrogen fixation technology and its associated research progress are reviewed.The production efficiency of various plasmas is summarized and compared.Eventually,the prospect of nitrogen fixation using low-temperature plasma in the future was proposed.