A new method for chemical pumping of gases has been developed using reactive alloys of Li with IIA metals in the liquid state. It is an answer to the need for ultra-high and extremely high vacuum without loose solid p...A new method for chemical pumping of gases has been developed using reactive alloys of Li with IIA metals in the liquid state. It is an answer to the need for ultra-high and extremely high vacuum without loose solid particles. Another application of this development is the production of high- and ultra-pure noble gases in a one-step process. Both of these solutions are unprecedented;they are based on a new gas/melt sorption interface that raises the overall bar of technical advances in the field to a higher level, simplifying sorption equipment and leading to cost savings.展开更多
AIM： To determine the serum levels of c-reactive protein （CRP）, transferrin （TRF）, a2-macroglobulin （A2M）, ceruloplasmin （CER）, al-acid glycoprotein （AAG）, prealbumin （P-ALB） and retinol-binding protein ...AIM： To determine the serum levels of c-reactive protein （CRP）, transferrin （TRF）, a2-macroglobulin （A2M）, ceruloplasmin （CER）, al-acid glycoprotein （AAG）, prealbumin （P-ALB） and retinol-binding protein （RBP） in gastric carcinoma patients and to explore their possible correlation with underlying Helicobacter pylori （H pylon） infection. METHODS： We measured the serum levels of CRP, TRF, A2M, CER, AAG, P-ALB, and RBP in 153 preoperative patients （93 males; mean age： 63.1±11.3 years） with non-cardia gastric adenocarcinoma and 19 healthy subjects. RESULTS： The levels of CRP, CER, RBP, and AAG in cancer patients were significantly higher than those in healthy controls （P〈0.0001）, while no difference was found regarding the TRF, P-ALB, and A2M levels. Cancer patients with H py/ori infection had significantly lower RBP values compared to non-infected ones （P〈0.0001） and also higher values of CRP and AAG （P = 0.09 andP = 0.08, respectively）. CONCLUSION： High serum levels of CRP, CER and AAG in cancer patients do not seem to be related to H pylori infection. Retinol-binding protein seems to discriminate between infected and non-infected patients with gastric carcinoma. Further studies are needed to explore if it is directly involved in the pathogenesis of the disease or is merely an epiphenomenon.展开更多
Direct ethanol fuel cells have attracted attention as an alternative energy technology due to several advantages such as high theoretical energy density and abundant supply of ethanol.In spite of the advantages,commer...Direct ethanol fuel cells have attracted attention as an alternative energy technology due to several advantages such as high theoretical energy density and abundant supply of ethanol.In spite of the advantages,commercialization of direct ethanol fuel cells is hampered by the relatively low performance caused by its slow oxidation kinetics and difficulty of complete oxidation.In this study,formate,which has relatively faster oxidation kinetics,was mixed with ethanol to compensate the latter’s sluggish kinetics.Effects of p H,concentration,scan rate,and temperature on the mixed reactants oxidation on Pd were investigated by electrochemical experiments such as potential sweep and potentiostatic methods.Furthermore,the potential of the mixed reactants as fuel was evaluated by single cell experiments.As a result,we demonstrate that mixing formate with ethanol results in enhanced power performance in a single cell system.展开更多
Single phase 0.76(Bi_(0.5)Na_(0.5))TiO_(3)–0.24SrTiO_(3) ferroelectric ceramics have been synthesized with homogenous anatase and hierarchical rutile TiO_(2) raw reactants(BNST-A and BNST-R).Either calcined powder pe...Single phase 0.76(Bi_(0.5)Na_(0.5))TiO_(3)–0.24SrTiO_(3) ferroelectric ceramics have been synthesized with homogenous anatase and hierarchical rutile TiO_(2) raw reactants(BNST-A and BNST-R).Either calcined powder persists the microstructure characteristics of raw reactants.As the result,when the sintering temperature increases from 1000 to 1200℃,the average grain size and density of BNST-A increase from 0.49 to 1.48μm and 5.02 to 5.61 g/cm^(3),while those of BNST-R from 0.86 to 1.44μm and 5.37 to 5.61 g/cm^(3).BNST-A illustrates a predominant ergodic relaxor state,and BNST-R prefers a non-ergodic relaxor state,as evidenced by the distinct polarization-electric field loops and current-electric field curves.Especially,such a distinct ferroelectric state is independent of sintering temperature.It is believed that the special hierarchical microstructure of rutile TiO_(2) reactant is beneficial to form denser ceramics with larger grains,and thus suppresses the contributions of polar nanoregions and defect-induced built-in field to ferroelectric property,leading to non-ergodic relaxor state.This work clearly demonstrates the nonnegligible effects of TiO_(2) reactants on the microstructure and properties of BNST ferroelectric ceramics.展开更多
Objectives: To define clinical differences in the acute phase response and serum acute phase reactants between gout, pseudogout and crystal-induced arthritis in the presence of non-articular infections (CAI). Patients...Objectives: To define clinical differences in the acute phase response and serum acute phase reactants between gout, pseudogout and crystal-induced arthritis in the presence of non-articular infections (CAI). Patients and Methods: Eleven patients with definite gout, 12 patients with pseudogout and 5 patients with CIA were included in the study. Results: The erythrocyte sedimentation rate (ESR) was significantly different between gout (68.2 ± 49.9 mm/Hr) and CIA (113.8 ± 37.2 mm/Hr) but not between gout and pseudogout (83.9 ± 45.6 mm/Hr) or between pseudogout and CIA. The C-reactive protein (CRP) was significantly increased between gout (10.1 ± 7.9 mg/dL) and pseudogout (18.9 ± 9.8 mg/dL), gout and CIA (36.5 ± 12.4 mg/dL) as well as between pseudogout and CIA. The peripheral white cell count was significantly different between gout (9.27 ± 3.7 k/μL) and CIA (16.5 ± 6.8 k/μL), and between pseudogout (8.9 ± 3.2 k/μL) and CIA. Conclusions: Measurement of ESR and CRP are helpful in crystal-induced arthritis. The CRP has more discriminating utility than the ESR in distinguishing between gout, pseudogout and CIA. Peripheral wbc is most useful for differentiating crystal-induced arthritis from CIA.展开更多
The increasingly serious climate issue compels urgent greenhouse gas mitigation strategies.As a budget,plentiful,renewable feedstock and major contributor to global warming,the large-scale catalytic transformation of ...The increasingly serious climate issue compels urgent greenhouse gas mitigation strategies.As a budget,plentiful,renewable feedstock and major contributor to global warming,the large-scale catalytic transformation of CO_(2)has attracted widespread attention from society due to its potential as a solution to the environment and energy crises.At present,catalytic hydrogenation of carbon dioxide to organic chemicals is the primary approach in its industrial applications.In recent decades,various materials containing Cu-,precious metal-,In-,Zn-,and Ga-based catalysts have been designed for CO_(2)hydrogenation to methanol.Likewise,great advances have been made in CO_(2)-to-chemicals,such as olefins,aromatics,and gasoline by combining CO_(2)-to-CH3OH with methanol transformation or tandem reaction of reverse water-gas shift and Fischer-Tropsch(FT)synthesis.This review exhibits the recent advances in the hydrogenation of CO_(2)-to-CH3OH including the catalyst system,CO_(2)activation,nature of active sites,intermediate species(formate or carboxyl),structure-activity relationship,and reaction mechanism.Finally,challenges and outlooks in CO_(2)hydrogenation to methanol are summarized.展开更多
It is well known that gravity may have a profound impact on the combustion process under certain conditions[1].The densities of the gaseous combustion products are typically 5-12 times lower than those of reactants.Un...It is well known that gravity may have a profound impact on the combustion process under certain conditions[1].The densities of the gaseous combustion products are typically 5-12 times lower than those of reactants.Under normal gravity conditions,the density difference generates buoyant forces that drive the flow,which affects the combustion process through flow-transport-chemistry interaction.For example,the buoyant convection in normal gravity causes the candle flame to be shaped like a teardrop while spherical candle flame is observed in microgravity.Recently,microgravity combustion has drawn great attention.A series of combustion experiments have been and will be conducted in the International Space Station and Chinese Space Station.In fact,significant progress has been made in microgravity combustion.For example,the discovery of steadily burning cool flames[2]in microgravity experiments was regarded as one of the"20 Breakthroughs from 20 Years of Science aboard the International Space Station".展开更多
Objective: To observe the effects of Xuebijing Injection (血必净注射液) in patients with severe pneumonia, and to explore the mechanism. Methods: Eighty cases of severe pneumonia are randomly assigned to the Xuebijing...Objective: To observe the effects of Xuebijing Injection (血必净注射液) in patients with severe pneumonia, and to explore the mechanism. Methods: Eighty cases of severe pneumonia are randomly assigned to the Xuebijing treatment (forty cases) and the control group (forty cases), with the same routine therapy provided in both groups. Clinical effective rates, inflammatory factors and organ function were observed in both groups. Results: The effective rate was higher in Xuebijing group than that of the control group (80.0% vs. 67.5%, P<0.05). As compared with the control group, the LDH, α1-AG, α1-AT levels and the peak body temperature decreased markedly with the Xuebijing treatment going, and the secretion of TNF-α, IL-6, IL-8 was suppressed in Xuebijing group; but no significant difference was found in leptin level. Conclusion: Xuebijing Injection may show a protective effect in patients with severe pneumonia. The mechanism is possibly with the decreased secretion of TNF-α, IL-6, and IL-8.展开更多
The need for the separation of azeotropic mixtures for the production of high-end chemicals and resource recovery has spurred significant research into the development of new separation methods in the chemical industr...The need for the separation of azeotropic mixtures for the production of high-end chemicals and resource recovery has spurred significant research into the development of new separation methods in the chemical industry.In this paper,a green and sustainable method for azeotrope separation is proposed based on a chemical-looping concept with the help of reversible-reaction-assisted distillation.The central concept in the chemical-looping separation(CLS)method is the selection of a reactant that can react with the azeotrope components and can also be recycled by the reverse reaction to close the loop and achieve cyclic azeotrope separation.This paper aims to provide an informative perspective on the fundamental theory and applications of the CLS method based on the separation principle,reactant selection,and case analysis,for example,the separation of alkenes,alkane,aromatics,and polyol products.In summary,we provide guidance and references for chemical separation process intensification in product refining and separation from azeotropic systems for the development of a more sustainable chemical industry.展开更多
One of the main problems in the flow-through gas purification technologies is related with continuous control of the outlet gas purity. The information concerning purity of the produced gas is on high demand, e.g., fo...One of the main problems in the flow-through gas purification technologies is related with continuous control of the outlet gas purity. The information concerning purity of the produced gas is on high demand, e.g., for processing systems integrated with gas purifiers. The positive solution of this problem has become possible only now due to the appearance of reactive getters (reactants) that serve as highly efficient sinks for gas impurities and our sorption model of the processes, which take place in gas purifiers with these reactants. According to the given model the appearance of a single valued functional connection between the purity of the gas product and the duration of the treatment of the gas flow by the sorbing powder is typical for any system Me -Y, where Me is a powder reactant and Y is an impurity gas. This strict correlation provides the mathematical justification to a simple method of determining the concentration of the impurity in the gas flow at the exit from the gas purifier. This method comes down to measuring of the quantity of the purified gas by a gas flow meter, the readings of which are graduated in the units of gas concentration.展开更多
The development of advanced and cost-effective methods is of prime importance for manufacturers of high purity gases. In this paper a new strategy in the development of gas flow purification technologies is described,...The development of advanced and cost-effective methods is of prime importance for manufacturers of high purity gases. In this paper a new strategy in the development of gas flow purification technologies is described, where instead of adsorbents reactants are used, in which not only the surface is used in gas capturing but the entire volume of the material. Moreover, the reactants are activated in the gas flow by a controlled mechanical tool, which keeps the sorption kinetics at the required highest level and reduces the unproductive losses of the consumed reactant almost to zero. The advantages of the method are demonstrated with the examples of two novel gas purification units that are distinguished with uncomplicated design, serviceability and ultimately high purification efficiency.展开更多
Sulfonium salts and sulfur ylides are important S(Ⅳ) motifs,and have displayed many unique reactivities to provide simple,effective,and often stereoselective synthesis toward sulfur containing compounds.Impressive de...Sulfonium salts and sulfur ylides are important S(Ⅳ) motifs,and have displayed many unique reactivities to provide simple,effective,and often stereoselective synthesis toward sulfur containing compounds.Impressive developments have been witnessed within this field during the past several years.In light of the increasing demand of organosulfur compounds across the range of chemical sciences,our aim of this review is to provide a concise overview of recent advances of sulfonium salt and sulfur ylide chemistry.Selected examples are organized in three parts on the basis of their role in organic reactions(reactants,intermediates and catalysts).展开更多
BACKGROUND Uncontrolled growth and loss of control over basic metabolic functions,leading to invasive proliferation and metastases,are the salient traits of malignant tumors in general and colorectal cancer in particu...BACKGROUND Uncontrolled growth and loss of control over basic metabolic functions,leading to invasive proliferation and metastases,are the salient traits of malignant tumors in general and colorectal cancer in particular.Invasion and metastases hinder effective tumor treatment.While surgical techniques and radiotherapy can be used to remove tumor focus,only chemotherapy can eliminate dispersed neoplastic cells.However,the efficacy of the latter method is limited in the advanced stages of the disease.Therefore,recognition of the mechanisms involved in neoplastic cell spreading is indispensable for developing effective therapies.AIM To use a number of biomarkers involved in cancer progression and identify a panel that could be used for effective early diagnosis.METHODS We recruited 185 patients with colorectal adenocarcinoma(98 men,87 women with median age 63).Thirty-five healthy controls were sex and age-matched.Dukes’staging was as follows:A=22,B=52,C=72,D=39.We analyzed patients'blood serum before surgery.We determined:(1)Cathepsin B(CB)with Barrett's method(fluorogenic substrate);(2)Leukocytic elastase(LE)in a complex with alpha 1 trypsin inhibitor(AAT)using the immunoenzymatic MERCK test;(3)Total sialic acid(TSA)with the colorimetric periodate-resorcinol method;(4)Lipid-bound sialic acid(LASA)with the colorimetric Taut's method;and(5)The antitrypsin activity(ATA)employing the colorimetric test.RESULTS In patients,the values of the five biochemical parameters were as follows:CB=16.1±8.8 mU/L,LE=875±598μg/L,TSA=99±31 mg%,LASA=0.68±0.33 mg%,and ATA=3211±1504 U/mL.Except for LASA,they were significantly greater than those of controls:CB=11.4±6.5 mU/L,LE=379±187μg/L,TSA=71.4±15.1 mg%,LASA=0.69±0.28 mg%,and ATA=2016±690 U/mL.For CB and LASA,the differences between the four Dukes’stages and controls were not statistically significant.The inter-stage differences for CB and LASA were also absent.The receiver operating characteristic(ROC)analysis revealed the potential diagnostic value of CB,TSA,and ATA.The area under ROC,sensitivity,and specificity for these three parameters were:0.85,72%,90%;0.75,66%,77%;and 0.77,63%,84%,respectively.The sensitivity and specificity for the threeparameter panel CB-TSA-ATA were equal to 88.2%and 100%,respectively.CONCLUSION The increased value of CB,TSA,and ATA parameters are associated with tumor biology,invasion,and metastasis of colorectal cancer.The presented evidence suggests the potential value of the CB-TSA-ATA biochemical marker panel in early diagnostics.展开更多
There is an increasing interest in bismuth carbonate(Bi2O2CO3,BOC)as a semiconductor photocatalyst.However,pure BOC strongly absorbs ultraviolet light,which drives a high recombination rate of charge carriers and ther...There is an increasing interest in bismuth carbonate(Bi2O2CO3,BOC)as a semiconductor photocatalyst.However,pure BOC strongly absorbs ultraviolet light,which drives a high recombination rate of charge carriers and thereby limits the overall photocatalysis efficiency.In this work,artificial oxygen vacancies(OV)were introduced into BOC(OV-BOC)to broaden the optical absorption range,increase the charge separation efficiency,and activate the reactants.The photocatalytic removal ratio of NO was increased significantly from 10.0%for pure BOC to 50.2%for OV-BOC because of the multiple roles played by the oxygen vacancies.These results imply that oxygen vacancies can facilitate the electron exchange between intermediates and the surface oxygen vacancies in OV-BOC,making them more easily destroyed by active radicals.In situ DRIFTS spectra in combination with electron spin resonance spectra and density functional theory calculations enabled unraveling of the conversion pathway for the photocatalytic NO oxidation on OV-BOC.It was found that oxygen vacancies could increase the production of active radicals and promote the transformation of NO into target products instead of toxic byproducts(NO2),thus the selectivity is significantly enhanced.This work provides a new strategy for enhancing photocatalytic activity and selectivity.展开更多
To date,investigations onto the regulation of reactants mass transfer has been paid much less attention in environmental catalysis.Herein,we demonstrated that by rationally designing the adsorption sites of multi-reac...To date,investigations onto the regulation of reactants mass transfer has been paid much less attention in environmental catalysis.Herein,we demonstrated that by rationally designing the adsorption sites of multi-reactants,the pollutant destruction efficiency,product selectivity,reaction stability and secondary pollution have been all affected in the catalytic chlorobenzene oxidation(CBCO).Experimental results revealed that the co-adsorption of chlo robenzene(CB)and gaseous O_(2)at the oxygen vacancies of CeO_(2)led to remarkably high CO_(2)generation,owning to their short mass transfer distance on the catalyst surface,while their separated adsorptions at Bronsted HZSM-5 and CeO_(2)vacancies resulted in a much lower CO_(2)generation,and produced significant polychlorinated byproducts in the off-gas.Howeve r,this separated adsorption model yielded superior long-term stability for the CeO_(2)/HZSM-5 catalyst,owning to the protection of CeO_(2)oxygen vacancies from Cl poisoning by the preferential adsorption of CB on the Bronsted acidic sites.This work unveils that design of environmental catalysts needs to consider both of the catalyst intrinsic property and reactant mass transfer;investigations of the latter could pave a new way for the development of highly efficient catalysts towards environmental pollution control.展开更多
Design of efficient catalysts for electrochemical reduction of carbon dioxide (CO_(2)) with high selectivity and activity is of great challenge, but significant for managing the global carbon balance. Herein, a series...Design of efficient catalysts for electrochemical reduction of carbon dioxide (CO_(2)) with high selectivity and activity is of great challenge, but significant for managing the global carbon balance. Herein, a series of three-dimensional (3D) single-atom metals anchored on graphene networks (3D SAM-G) with open-pore structure were successfully mass-produced via a facile in-situ calcination technique assisted by NaCl template. As-obtained 3D SANi-G electrode delivers excellent CO Faradaic efficiency (FE) of >96% in the potential range of −0.6 to −0.9 V versus reversible hydrogen electrode (RHE) and a high current density of 66.27 mA cm^(−2) at −1.0 V versus RHE, outperforming most of the previously reported catalysts tested in H-type cells. Simulations indicate that enhanced mass transport within the 3D open-pore structure effectively increases the catalytically active sites, which in turn leads to simultaneous enhancement on selectivity and activity of 3D SANi-G toward CO_(2) electroreduction. The cost-effective synthesis approach together with the microstructure design concept inspires new insights for the development of efficient electrocatalysts.展开更多
In this work,monodisperseβ-NaLuF_(4):Yb,Er microcrystals with intense upconversion emission were synthesized via a modified hydrothermal method.With the increase of reactant concentration,their production yield is in...In this work,monodisperseβ-NaLuF_(4):Yb,Er microcrystals with intense upconversion emission were synthesized via a modified hydrothermal method.With the increase of reactant concentration,their production yield is increased obviously,and the upconversion emission intensity inβ-NaLuF_(4):Yb,Er microcrystals is also enhanced significantly.The luminescence enhancement should be attributed to minimal internal OH defects,validated by a combination of analytical X-ray diffraction(XRD),energy dispersive spectrum(EDS),and Eu^(3+)structural probe measurements.We also reveal that high Na^(+):RE~(3+)ratio in theβ-NaLuF_(4):Yb,Er microcrystals prepared under Na^(~)+-rich reaction will arouse the increased repulsive energy ofβ-NaLuF_(4)microcrystals between F^(~)-and OH^(~)-anions and then facilitate the substitution of large OH^(-)ions by small F^(~)-ions under F^(~)--rich reaction conditions.Minimal OH^(-)concentrations can limit nonradiative relaxation and promote excitation energy harvesting for high upconversion efficiency.The presented results not only offer a facile method for the simultaneous production yield and luminescence intensity increase ofβ-NaREF_(4)microcrystals,but also uncover a better insight into the upconversion emission alterations,which is favorable to broaden their practical applications.展开更多
Micro-mixing is an important mechanism, which works simultaneously with macro-mixing in chemical reactors in process industries, for achieving the best selectivity with respect to desired products. In about a half cen...Micro-mixing is an important mechanism, which works simultaneously with macro-mixing in chemical reactors in process industries, for achieving the best selectivity with respect to desired products. In about a half century, a huge amount of data and knowledge has been accumulated from theoretical and experimental studies on micromixing. Nevertheless, those results are mostly composites of simplified theoretical and empirical models, and the true nature of interactions of flow inhomogeneity and micro-mixing with chemical reaction has not been fully unveiled. This article reviews the progress in micro-mixing study in chemical reactors to date. A few important topics related to the nature, experimental evaluation, and numerical simulation of micro-mixing are addressed.Some suggestions are given hopefully to motivate more chemical engineers to devote their efforts to better understanding of micro-mixing in chemical reactors.展开更多
In this paper,a 60 kW proton exchange membrane fuel cell(PEMFC) generation system is modeled in order to design the system parameters and investigate the static and dynamic characteristics for control purposes.To achi...In this paper,a 60 kW proton exchange membrane fuel cell(PEMFC) generation system is modeled in order to design the system parameters and investigate the static and dynamic characteristics for control purposes.To achieve an overall system model,the system is divided into five modules:the PEMFC stack(anode and cathode flows,membrane hydration,and stack voltage and power),cathode air supply(air compressor,supply manifold,cooler,and humidifier),anode fuel supply(hydrogen valve and humidifier),cathode exhaust exit(exit manifold and water return),and power conditioning(DC/DC and DC/AC) modules.Using a combination of empirical and physical modeling techniques,the model is developed to set the operation conditions of current,temperature,and cathode and anode gas flows and pressures,which have major impacts on system performance.The current model is based on a 60 kW PEMFC power plant designed for residential applications and takes account of the electrochemical and thermal aspects of chemical reactions within the stack as well as flows of reactants across the system.The simulation tests show that the system model can represent the static and dynamic characteristics of a 60 kW PEMFC generation system,which is mathematically simple for system parameters and control designs.展开更多
This paper studies the influence of the reagent vibration on the reaction O（1D）＋HF→HO＋F by using a quasiclassical trajectory method on the new ab initio 1A＇ ground singlet potential energy surface （Gomez-Carras...This paper studies the influence of the reagent vibration on the reaction O（1D）＋HF→HO＋F by using a quasiclassical trajectory method on the new ab initio 1A＇ ground singlet potential energy surface （Gomez-Carrasco et al 2007 Chem. Phys. Lett. 435 188 193）. The product angular distributions which reflect the vector correlation are calculated. Four polarization-dependent differential cross sections （PDDCSs） which are sensitive to many photoinitiated bimolecular reaction experiments are presented in the center of the mass frame, respectively. The differential cross section indicates that the OH product mainly tends to the forward scattering, and other PDDCSs are also influenced by the vibration levels of HF.展开更多
文摘A new method for chemical pumping of gases has been developed using reactive alloys of Li with IIA metals in the liquid state. It is an answer to the need for ultra-high and extremely high vacuum without loose solid particles. Another application of this development is the production of high- and ultra-pure noble gases in a one-step process. Both of these solutions are unprecedented;they are based on a new gas/melt sorption interface that raises the overall bar of technical advances in the field to a higher level, simplifying sorption equipment and leading to cost savings.
文摘AIM： To determine the serum levels of c-reactive protein （CRP）, transferrin （TRF）, a2-macroglobulin （A2M）, ceruloplasmin （CER）, al-acid glycoprotein （AAG）, prealbumin （P-ALB） and retinol-binding protein （RBP） in gastric carcinoma patients and to explore their possible correlation with underlying Helicobacter pylori （H pylon） infection. METHODS： We measured the serum levels of CRP, TRF, A2M, CER, AAG, P-ALB, and RBP in 153 preoperative patients （93 males; mean age： 63.1±11.3 years） with non-cardia gastric adenocarcinoma and 19 healthy subjects. RESULTS： The levels of CRP, CER, RBP, and AAG in cancer patients were significantly higher than those in healthy controls （P〈0.0001）, while no difference was found regarding the TRF, P-ALB, and A2M levels. Cancer patients with H py/ori infection had significantly lower RBP values compared to non-infected ones （P〈0.0001） and also higher values of CRP and AAG （P = 0.09 andP = 0.08, respectively）. CONCLUSION： High serum levels of CRP, CER and AAG in cancer patients do not seem to be related to H pylori infection. Retinol-binding protein seems to discriminate between infected and non-infected patients with gastric carcinoma. Further studies are needed to explore if it is directly involved in the pathogenesis of the disease or is merely an epiphenomenon.
基金supported by the New & Renewable Energy Core Technology Program of the Korea Institute of Energy Technology Evaluation and Planning(KETEP)granted financial resource from the Ministry of Trade,Industry & Energy,Republic of Korea(20153030031720)
文摘Direct ethanol fuel cells have attracted attention as an alternative energy technology due to several advantages such as high theoretical energy density and abundant supply of ethanol.In spite of the advantages,commercialization of direct ethanol fuel cells is hampered by the relatively low performance caused by its slow oxidation kinetics and difficulty of complete oxidation.In this study,formate,which has relatively faster oxidation kinetics,was mixed with ethanol to compensate the latter’s sluggish kinetics.Effects of p H,concentration,scan rate,and temperature on the mixed reactants oxidation on Pd were investigated by electrochemical experiments such as potential sweep and potentiostatic methods.Furthermore,the potential of the mixed reactants as fuel was evaluated by single cell experiments.As a result,we demonstrate that mixing formate with ethanol results in enhanced power performance in a single cell system.
基金supported by the National Key R&D Program of China(No.2020YFA0711504)the National Natural Science Foundation of China(Nos.12174179,51721001)+1 种基金the Natural Science Foundation of Jiangsu Province(No.BK20221251)the Dengfeng B project of Nanjing University。
文摘Single phase 0.76(Bi_(0.5)Na_(0.5))TiO_(3)–0.24SrTiO_(3) ferroelectric ceramics have been synthesized with homogenous anatase and hierarchical rutile TiO_(2) raw reactants(BNST-A and BNST-R).Either calcined powder persists the microstructure characteristics of raw reactants.As the result,when the sintering temperature increases from 1000 to 1200℃,the average grain size and density of BNST-A increase from 0.49 to 1.48μm and 5.02 to 5.61 g/cm^(3),while those of BNST-R from 0.86 to 1.44μm and 5.37 to 5.61 g/cm^(3).BNST-A illustrates a predominant ergodic relaxor state,and BNST-R prefers a non-ergodic relaxor state,as evidenced by the distinct polarization-electric field loops and current-electric field curves.Especially,such a distinct ferroelectric state is independent of sintering temperature.It is believed that the special hierarchical microstructure of rutile TiO_(2) reactant is beneficial to form denser ceramics with larger grains,and thus suppresses the contributions of polar nanoregions and defect-induced built-in field to ferroelectric property,leading to non-ergodic relaxor state.This work clearly demonstrates the nonnegligible effects of TiO_(2) reactants on the microstructure and properties of BNST ferroelectric ceramics.
文摘Objectives: To define clinical differences in the acute phase response and serum acute phase reactants between gout, pseudogout and crystal-induced arthritis in the presence of non-articular infections (CAI). Patients and Methods: Eleven patients with definite gout, 12 patients with pseudogout and 5 patients with CIA were included in the study. Results: The erythrocyte sedimentation rate (ESR) was significantly different between gout (68.2 ± 49.9 mm/Hr) and CIA (113.8 ± 37.2 mm/Hr) but not between gout and pseudogout (83.9 ± 45.6 mm/Hr) or between pseudogout and CIA. The C-reactive protein (CRP) was significantly increased between gout (10.1 ± 7.9 mg/dL) and pseudogout (18.9 ± 9.8 mg/dL), gout and CIA (36.5 ± 12.4 mg/dL) as well as between pseudogout and CIA. The peripheral white cell count was significantly different between gout (9.27 ± 3.7 k/μL) and CIA (16.5 ± 6.8 k/μL), and between pseudogout (8.9 ± 3.2 k/μL) and CIA. Conclusions: Measurement of ESR and CRP are helpful in crystal-induced arthritis. The CRP has more discriminating utility than the ESR in distinguishing between gout, pseudogout and CIA. Peripheral wbc is most useful for differentiating crystal-induced arthritis from CIA.
基金supported by the National Key R&D Program of China(2022YFA1504500,2022YFB4003100)the National Natural Science Foundation of China(U21B2092,22072162,22202213,22402210)+1 种基金the International Partnership Program of Chinese Academy of Sciences(172GJHZ2022028MI)Hua Dian Liaoning Energy Development CO.,LTD.(CHDKJ24-04-02-223).
文摘The increasingly serious climate issue compels urgent greenhouse gas mitigation strategies.As a budget,plentiful,renewable feedstock and major contributor to global warming,the large-scale catalytic transformation of CO_(2)has attracted widespread attention from society due to its potential as a solution to the environment and energy crises.At present,catalytic hydrogenation of carbon dioxide to organic chemicals is the primary approach in its industrial applications.In recent decades,various materials containing Cu-,precious metal-,In-,Zn-,and Ga-based catalysts have been designed for CO_(2)hydrogenation to methanol.Likewise,great advances have been made in CO_(2)-to-chemicals,such as olefins,aromatics,and gasoline by combining CO_(2)-to-CH3OH with methanol transformation or tandem reaction of reverse water-gas shift and Fischer-Tropsch(FT)synthesis.This review exhibits the recent advances in the hydrogenation of CO_(2)-to-CH3OH including the catalyst system,CO_(2)activation,nature of active sites,intermediate species(formate or carboxyl),structure-activity relationship,and reaction mechanism.Finally,challenges and outlooks in CO_(2)hydrogenation to methanol are summarized.
文摘It is well known that gravity may have a profound impact on the combustion process under certain conditions[1].The densities of the gaseous combustion products are typically 5-12 times lower than those of reactants.Under normal gravity conditions,the density difference generates buoyant forces that drive the flow,which affects the combustion process through flow-transport-chemistry interaction.For example,the buoyant convection in normal gravity causes the candle flame to be shaped like a teardrop while spherical candle flame is observed in microgravity.Recently,microgravity combustion has drawn great attention.A series of combustion experiments have been and will be conducted in the International Space Station and Chinese Space Station.In fact,significant progress has been made in microgravity combustion.For example,the discovery of steadily burning cool flames[2]in microgravity experiments was regarded as one of the"20 Breakthroughs from 20 Years of Science aboard the International Space Station".
文摘Objective: To observe the effects of Xuebijing Injection (血必净注射液) in patients with severe pneumonia, and to explore the mechanism. Methods: Eighty cases of severe pneumonia are randomly assigned to the Xuebijing treatment (forty cases) and the control group (forty cases), with the same routine therapy provided in both groups. Clinical effective rates, inflammatory factors and organ function were observed in both groups. Results: The effective rate was higher in Xuebijing group than that of the control group (80.0% vs. 67.5%, P<0.05). As compared with the control group, the LDH, α1-AG, α1-AT levels and the peak body temperature decreased markedly with the Xuebijing treatment going, and the secretion of TNF-α, IL-6, IL-8 was suppressed in Xuebijing group; but no significant difference was found in leptin level. Conclusion: Xuebijing Injection may show a protective effect in patients with severe pneumonia. The mechanism is possibly with the decreased secretion of TNF-α, IL-6, and IL-8.
基金The authors acknowledge financial support from the National Key Research and Development Program of China(2018YFB0604900)the National Natural Science Foundation of China(21690084 and 21878219).
文摘The need for the separation of azeotropic mixtures for the production of high-end chemicals and resource recovery has spurred significant research into the development of new separation methods in the chemical industry.In this paper,a green and sustainable method for azeotrope separation is proposed based on a chemical-looping concept with the help of reversible-reaction-assisted distillation.The central concept in the chemical-looping separation(CLS)method is the selection of a reactant that can react with the azeotrope components and can also be recycled by the reverse reaction to close the loop and achieve cyclic azeotrope separation.This paper aims to provide an informative perspective on the fundamental theory and applications of the CLS method based on the separation principle,reactant selection,and case analysis,for example,the separation of alkenes,alkane,aromatics,and polyol products.In summary,we provide guidance and references for chemical separation process intensification in product refining and separation from azeotropic systems for the development of a more sustainable chemical industry.
文摘One of the main problems in the flow-through gas purification technologies is related with continuous control of the outlet gas purity. The information concerning purity of the produced gas is on high demand, e.g., for processing systems integrated with gas purifiers. The positive solution of this problem has become possible only now due to the appearance of reactive getters (reactants) that serve as highly efficient sinks for gas impurities and our sorption model of the processes, which take place in gas purifiers with these reactants. According to the given model the appearance of a single valued functional connection between the purity of the gas product and the duration of the treatment of the gas flow by the sorbing powder is typical for any system Me -Y, where Me is a powder reactant and Y is an impurity gas. This strict correlation provides the mathematical justification to a simple method of determining the concentration of the impurity in the gas flow at the exit from the gas purifier. This method comes down to measuring of the quantity of the purified gas by a gas flow meter, the readings of which are graduated in the units of gas concentration.
文摘The development of advanced and cost-effective methods is of prime importance for manufacturers of high purity gases. In this paper a new strategy in the development of gas flow purification technologies is described, where instead of adsorbents reactants are used, in which not only the surface is used in gas capturing but the entire volume of the material. Moreover, the reactants are activated in the gas flow by a controlled mechanical tool, which keeps the sorption kinetics at the required highest level and reduces the unproductive losses of the consumed reactant almost to zero. The advantages of the method are demonstrated with the examples of two novel gas purification units that are distinguished with uncomplicated design, serviceability and ultimately high purification efficiency.
基金the support from the National Natural Science Foundation of China(No.21702013)the Fundamental Research Funds for the Central Universities(Nos.XK1802-6 and buctrc201721)at the BUCT.JTan and Y.Liu are thankful for the support from the Open Project Program(No.SPFW2019YB06)of Beijing Key Laboratory of Flavor Chemistry,Beijing Technology and Business University(BTBU)。
文摘Sulfonium salts and sulfur ylides are important S(Ⅳ) motifs,and have displayed many unique reactivities to provide simple,effective,and often stereoselective synthesis toward sulfur containing compounds.Impressive developments have been witnessed within this field during the past several years.In light of the increasing demand of organosulfur compounds across the range of chemical sciences,our aim of this review is to provide a concise overview of recent advances of sulfonium salt and sulfur ylide chemistry.Selected examples are organized in three parts on the basis of their role in organic reactions(reactants,intermediates and catalysts).
文摘BACKGROUND Uncontrolled growth and loss of control over basic metabolic functions,leading to invasive proliferation and metastases,are the salient traits of malignant tumors in general and colorectal cancer in particular.Invasion and metastases hinder effective tumor treatment.While surgical techniques and radiotherapy can be used to remove tumor focus,only chemotherapy can eliminate dispersed neoplastic cells.However,the efficacy of the latter method is limited in the advanced stages of the disease.Therefore,recognition of the mechanisms involved in neoplastic cell spreading is indispensable for developing effective therapies.AIM To use a number of biomarkers involved in cancer progression and identify a panel that could be used for effective early diagnosis.METHODS We recruited 185 patients with colorectal adenocarcinoma(98 men,87 women with median age 63).Thirty-five healthy controls were sex and age-matched.Dukes’staging was as follows:A=22,B=52,C=72,D=39.We analyzed patients'blood serum before surgery.We determined:(1)Cathepsin B(CB)with Barrett's method(fluorogenic substrate);(2)Leukocytic elastase(LE)in a complex with alpha 1 trypsin inhibitor(AAT)using the immunoenzymatic MERCK test;(3)Total sialic acid(TSA)with the colorimetric periodate-resorcinol method;(4)Lipid-bound sialic acid(LASA)with the colorimetric Taut's method;and(5)The antitrypsin activity(ATA)employing the colorimetric test.RESULTS In patients,the values of the five biochemical parameters were as follows:CB=16.1±8.8 mU/L,LE=875±598μg/L,TSA=99±31 mg%,LASA=0.68±0.33 mg%,and ATA=3211±1504 U/mL.Except for LASA,they were significantly greater than those of controls:CB=11.4±6.5 mU/L,LE=379±187μg/L,TSA=71.4±15.1 mg%,LASA=0.69±0.28 mg%,and ATA=2016±690 U/mL.For CB and LASA,the differences between the four Dukes’stages and controls were not statistically significant.The inter-stage differences for CB and LASA were also absent.The receiver operating characteristic(ROC)analysis revealed the potential diagnostic value of CB,TSA,and ATA.The area under ROC,sensitivity,and specificity for these three parameters were:0.85,72%,90%;0.75,66%,77%;and 0.77,63%,84%,respectively.The sensitivity and specificity for the threeparameter panel CB-TSA-ATA were equal to 88.2%and 100%,respectively.CONCLUSION The increased value of CB,TSA,and ATA parameters are associated with tumor biology,invasion,and metastasis of colorectal cancer.The presented evidence suggests the potential value of the CB-TSA-ATA biochemical marker panel in early diagnostics.
基金supported by the National Key R&D Program of China(2016YFC02047)the National Natural Science Foundation of China(21822601,21777011,and 21501016)+3 种基金the Graduate Research and Innovation Foundation of Chongqing(CYS18019)the Innovative Research Team of Chongqing(CXTDG201602014)the Natural Science Foundation of Chongqing(cstc2017jcyjBX0052)the National Special Supporting National Plan for High-Level~~
文摘There is an increasing interest in bismuth carbonate(Bi2O2CO3,BOC)as a semiconductor photocatalyst.However,pure BOC strongly absorbs ultraviolet light,which drives a high recombination rate of charge carriers and thereby limits the overall photocatalysis efficiency.In this work,artificial oxygen vacancies(OV)were introduced into BOC(OV-BOC)to broaden the optical absorption range,increase the charge separation efficiency,and activate the reactants.The photocatalytic removal ratio of NO was increased significantly from 10.0%for pure BOC to 50.2%for OV-BOC because of the multiple roles played by the oxygen vacancies.These results imply that oxygen vacancies can facilitate the electron exchange between intermediates and the surface oxygen vacancies in OV-BOC,making them more easily destroyed by active radicals.In situ DRIFTS spectra in combination with electron spin resonance spectra and density functional theory calculations enabled unraveling of the conversion pathway for the photocatalytic NO oxidation on OV-BOC.It was found that oxygen vacancies could increase the production of active radicals and promote the transformation of NO into target products instead of toxic byproducts(NO2),thus the selectivity is significantly enhanced.This work provides a new strategy for enhancing photocatalytic activity and selectivity.
基金financially supported by the National Key R&D Program of China(No.2016YFC0202200)the National Natural Science Foundation of China(Nos.21777140,21922607)the Outstanding Youth Project of Zhejiang Natural Science Foundation(No.LR19E080004)。
文摘To date,investigations onto the regulation of reactants mass transfer has been paid much less attention in environmental catalysis.Herein,we demonstrated that by rationally designing the adsorption sites of multi-reactants,the pollutant destruction efficiency,product selectivity,reaction stability and secondary pollution have been all affected in the catalytic chlorobenzene oxidation(CBCO).Experimental results revealed that the co-adsorption of chlo robenzene(CB)and gaseous O_(2)at the oxygen vacancies of CeO_(2)led to remarkably high CO_(2)generation,owning to their short mass transfer distance on the catalyst surface,while their separated adsorptions at Bronsted HZSM-5 and CeO_(2)vacancies resulted in a much lower CO_(2)generation,and produced significant polychlorinated byproducts in the off-gas.Howeve r,this separated adsorption model yielded superior long-term stability for the CeO_(2)/HZSM-5 catalyst,owning to the protection of CeO_(2)oxygen vacancies from Cl poisoning by the preferential adsorption of CB on the Bronsted acidic sites.This work unveils that design of environmental catalysts needs to consider both of the catalyst intrinsic property and reactant mass transfer;investigations of the latter could pave a new way for the development of highly efficient catalysts towards environmental pollution control.
基金The authors acknowledge the support from the National Natural Science Foundation of China(51872012)the Key Technologies Research and Development Program of China(Grant No.2018YFA-900).
文摘Design of efficient catalysts for electrochemical reduction of carbon dioxide (CO_(2)) with high selectivity and activity is of great challenge, but significant for managing the global carbon balance. Herein, a series of three-dimensional (3D) single-atom metals anchored on graphene networks (3D SAM-G) with open-pore structure were successfully mass-produced via a facile in-situ calcination technique assisted by NaCl template. As-obtained 3D SANi-G electrode delivers excellent CO Faradaic efficiency (FE) of >96% in the potential range of −0.6 to −0.9 V versus reversible hydrogen electrode (RHE) and a high current density of 66.27 mA cm^(−2) at −1.0 V versus RHE, outperforming most of the previously reported catalysts tested in H-type cells. Simulations indicate that enhanced mass transport within the 3D open-pore structure effectively increases the catalytically active sites, which in turn leads to simultaneous enhancement on selectivity and activity of 3D SANi-G toward CO_(2) electroreduction. The cost-effective synthesis approach together with the microstructure design concept inspires new insights for the development of efficient electrocatalysts.
基金Project supported by the National Natural Science Foundation of China(11504317,51503177)the International Partnership Program of Chinese Academy of Sciences(121522KYSB20190022)。
文摘In this work,monodisperseβ-NaLuF_(4):Yb,Er microcrystals with intense upconversion emission were synthesized via a modified hydrothermal method.With the increase of reactant concentration,their production yield is increased obviously,and the upconversion emission intensity inβ-NaLuF_(4):Yb,Er microcrystals is also enhanced significantly.The luminescence enhancement should be attributed to minimal internal OH defects,validated by a combination of analytical X-ray diffraction(XRD),energy dispersive spectrum(EDS),and Eu^(3+)structural probe measurements.We also reveal that high Na^(+):RE~(3+)ratio in theβ-NaLuF_(4):Yb,Er microcrystals prepared under Na^(~)+-rich reaction will arouse the increased repulsive energy ofβ-NaLuF_(4)microcrystals between F^(~)-and OH^(~)-anions and then facilitate the substitution of large OH^(-)ions by small F^(~)-ions under F^(~)--rich reaction conditions.Minimal OH^(-)concentrations can limit nonradiative relaxation and promote excitation energy harvesting for high upconversion efficiency.The presented results not only offer a facile method for the simultaneous production yield and luminescence intensity increase ofβ-NaREF_(4)microcrystals,but also uncover a better insight into the upconversion emission alterations,which is favorable to broaden their practical applications.
基金Supported by the National Natural Science Foundation of China(21376243,91434126)National Key Research and Development Program(2016YFB0301702)+1 种基金the State Key Development Program for Basic Research of China(2012CB224806)Jiangsu National Synergetic Innovation Center for Advanced Materials
文摘Micro-mixing is an important mechanism, which works simultaneously with macro-mixing in chemical reactors in process industries, for achieving the best selectivity with respect to desired products. In about a half century, a huge amount of data and knowledge has been accumulated from theoretical and experimental studies on micromixing. Nevertheless, those results are mostly composites of simplified theoretical and empirical models, and the true nature of interactions of flow inhomogeneity and micro-mixing with chemical reaction has not been fully unveiled. This article reviews the progress in micro-mixing study in chemical reactors to date. A few important topics related to the nature, experimental evaluation, and numerical simulation of micro-mixing are addressed.Some suggestions are given hopefully to motivate more chemical engineers to devote their efforts to better understanding of micro-mixing in chemical reactors.
基金Project supported by the National Natural Science Foundation of China (No.10472101)the Specialized Research Fund for the Doctoral Program of Higher Education of China (No.20070335184)
文摘In this paper,a 60 kW proton exchange membrane fuel cell(PEMFC) generation system is modeled in order to design the system parameters and investigate the static and dynamic characteristics for control purposes.To achieve an overall system model,the system is divided into five modules:the PEMFC stack(anode and cathode flows,membrane hydration,and stack voltage and power),cathode air supply(air compressor,supply manifold,cooler,and humidifier),anode fuel supply(hydrogen valve and humidifier),cathode exhaust exit(exit manifold and water return),and power conditioning(DC/DC and DC/AC) modules.Using a combination of empirical and physical modeling techniques,the model is developed to set the operation conditions of current,temperature,and cathode and anode gas flows and pressures,which have major impacts on system performance.The current model is based on a 60 kW PEMFC power plant designed for residential applications and takes account of the electrochemical and thermal aspects of chemical reactions within the stack as well as flows of reactants across the system.The simulation tests show that the system model can represent the static and dynamic characteristics of a 60 kW PEMFC generation system,which is mathematically simple for system parameters and control designs.
基金Project supported by the National Natural Science Foundation of China (Grant No 10574083)the Natural Science Foundation of Shandong Province of China (Grant No Y2006A23)partially by the National Basic Research Program of China (GrantNo 2006CB806000)
文摘This paper studies the influence of the reagent vibration on the reaction O（1D）＋HF→HO＋F by using a quasiclassical trajectory method on the new ab initio 1A＇ ground singlet potential energy surface （Gomez-Carrasco et al 2007 Chem. Phys. Lett. 435 188 193）. The product angular distributions which reflect the vector correlation are calculated. Four polarization-dependent differential cross sections （PDDCSs） which are sensitive to many photoinitiated bimolecular reaction experiments are presented in the center of the mass frame, respectively. The differential cross section indicates that the OH product mainly tends to the forward scattering, and other PDDCSs are also influenced by the vibration levels of HF.
