AIM: To study the effect of H2 gas on liver injury in massive hepatectomy using the Intermittent Pringle maneuver in swine. METHODS: Male Bama pigs (n = 14) treated with ketamine hydrochloride and Sumianxin Ⅱ as ...AIM: To study the effect of H2 gas on liver injury in massive hepatectomy using the Intermittent Pringle maneuver in swine. METHODS: Male Bama pigs (n = 14) treated with ketamine hydrochloride and Sumianxin Ⅱ as induc- tion drugs followed by inhalation anesthesia with 2% isoflurane, underwent 70% hepatotectomy with loss of bleeding less than 50 mL, and with hepatic pedicle occlusion for 20 min, were divided into two groups: Hydrogen-group (n = 7), the pigs with inhalation of 2% hydrogen by the tracheal intubation during major hepa- totectomy; Contrast-group (n= 7), underwent 70% hepatotectomy without inhalation of hydrogen. Hemo- dynamic changes and plasma concentrations of alanine aminotransferase (ALT), aspartate aminotransferase (AST), hyaluronic acid (HA), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and malondialdehyde (MDA) in liver tissue were measured at pre-operation, post-hepatotectomy (PH) 1 h and 3 h. The apoptosis and proliferating cell nuclear antigen (PCNA) expres- sion in liver remnant were evaluated at PH 3 h. Then we compared the two groups by these marks to evalu- ate the effect of the hydrogen in the liver injury during major hepatotectomy with the Pringle Maneuver in the swine. RESULTS: There were no significant differences in body weight, blood loss and removal liver weight be- tween the two groups. There was no significant differ- ence in changes of portal vein pressure between two groups at pre-operation, PH 30 min, but in hydrogen gas treated-group it slightly decrease and lower than its in Contrast-group at PH 3 h, although there were no significant difference (P = 0.655). ALT and AST in Hydrogen-group was significantly lower comparing to Contrast-group (P = 0.036, P = 0.011, vs P = 0.032, P = 0.013) at PH 1 h and 3 h, although the two groups all increased. The MDA level increased between the two group at PH i h and 3 h. In the hydrogen gas treated- group, the MDA level was not significantly significant at pre-operation and significantly low at PH 1 h and 3 h comparing to Contrast-group (P = 0.0005, P = 0.0004). In Hydrogen-group, the HA level was also significantly low to Contrast-group (P = 0.0005, P = 0.0005) al- though the two groups all increased at PH 1 h and 3 h. The expression of cluster of differentiation molecule 31 molecules Hydrogen-group was low to Contrast-group. However, PCNA index (%) was not statistically signifi- cant between the two groups (P = 0.802). Micropho- tometric evaluation of apoptotic index (AI) in terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling-stained tissue after hepatotectomy for 3h, the AI% level in the hydrogen was significantly low to Contrast-group (P = 0.012). There were no significant difference between Hydrogen-group and Contrast- group at pre-operation (P = 0.653, P = 0.423), but after massive hepatotectomy, the TNF-α and IL-6 levels increase, and its in Hydrogen-group was significantly low compared with Contrast-group (P = 0.022, P = 0.013, vs P = 0.016, P= 0.012), respectively. Hydro- gen-gas inhalation reduce levels of these markers and relieved morphological liver injury and apoptosis.CONCLUSION: H2 gas attenuates markedly ischemia and portal hyperperfusion injury in pigs with massive hepatotectomy, possibly by the reduction of inflamma- tion and oxidative stress, maybe a potential agent for treatment in clinic.展开更多
The fracture behavior of disordered and ordered Ni4Mo alloy was investigated by tensile tests in hydrogen gas or during hydrogen charging. The results show that the ductility of the disordered alloy decreased slightly...The fracture behavior of disordered and ordered Ni4Mo alloy was investigated by tensile tests in hydrogen gas or during hydrogen charging. The results show that the ductility of the disordered alloy decreased slightly with the hydrogen pressure increasing, while that of the ordered alloy decreased rapidly with the hydrogen pressure increasing. However, the ductility of both disordered and ordered alloys reduced similarly seriously with the charging current density increasing. Therefore, the mechanism of order-induced embrittlement of Ni4 Mo alloy in hydrogen gas is supposed to be that atomic order accelerates the kinetics of the catalytic reaction for the dissociation of molecular H2 into atomic H.展开更多
Current study reports a rapid one-pot non-hydrolytic condition in the synthesis of Sn O2QDs nanopowder using tin(II) stearate(Sn(St)2) as environmentally-benign organometallic precursor,which is an unprecedentedly emp...Current study reports a rapid one-pot non-hydrolytic condition in the synthesis of Sn O2QDs nanopowder using tin(II) stearate(Sn(St)2) as environmentally-benign organometallic precursor,which is an unprecedentedly employed-compound in preceding Sn O2nanopowder productions.The as-synthesized Sn O2QDs that are hydrophobic can be easily transferred from organic solvent to aqueous solution through a robust ligand exchange method.The stearate-capping ligands on the surface of QDs can be replaced by beta-cyclodextrin(β-CD) and eventually render the QDs highly water soluble,which ultimately make it exhibit bi-functionality for different liquid medium applications.Structural characterizations reveal that the bi-functional QDs are indeed well-matched with the standard rutile Sn O2cassiterite phase without the presence of any impurities.The QDs can be interchangeably used as photocatalyst for both aqueous and non-aqueous phase,where it shows significant enhancement of hydrogen gas production as compared to that of commercial Sn O2nanopowder.展开更多
Zinc oxide (ZnO) nanorods are prepared using equimolar solution of zinc nitrate ((Zn(NO3)2) and hexamethylenete- tramine (C6HleN4) by the hydrothermal technique at 80 ~C for 12 h. Epitaxial growth is explored...Zinc oxide (ZnO) nanorods are prepared using equimolar solution of zinc nitrate ((Zn(NO3)2) and hexamethylenete- tramine (C6HleN4) by the hydrothermal technique at 80 ~C for 12 h. Epitaxial growth is explored by X-ray diffraction (XRD) patterns, revealing that the ZnO nanorods have a hexagonal (wurtzite) structure. Absorption spectra of ZnO are measured by UV-visible spectrometer. The surface morphology is investigated by field emission scanning electron mi- croscopy (FESEM). The synthesized ZnO nanorods are used for detecting the 150 ~C hydrogen gas with a concentration over 1000 ppm. The obtained results show a reversible response. The influence of operating temperature on hydrogen gas detecting characteristic of ZnO nanorods is also investigated.展开更多
This study deals with the optimization of best working conditions in molten melt for the production of hydrogen(H2) gas.Limited research has been carried out on how electrochemical process occurs through steam splitti...This study deals with the optimization of best working conditions in molten melt for the production of hydrogen(H2) gas.Limited research has been carried out on how electrochemical process occurs through steam splitting via molten hydroxide.54 combinations of cathode,anode,temperature and voltage have been investigated for the optimization of best working conditions with molten hydroxide for hydrogen gas production.All these electrochemical investigations were carried out at 225 to 300℃ temperature and 1.5 to 2.5 V applied voltage values.The current efficiency of 90.5,80.0 and 68.6% has been achieved using stainless steel anodic cell with nickel,stainless steel and platinum working cathode respectively.For nickel cathode,an increase in the current directly affected the hydrogen gas flow rate at cathode.It can be hypothesized from the noted results that increase in current is directly proportional to operating temperature and applied voltage.Higher values were noted when the applied voltages increased from 1.5 to 2.5 V at 300℃,the flow rate of hydrogen gas increased from 1.5 to 11.3 cm^(3) min^(-1),1.0 to 13 cm^(3) min^(-1) in case of electrolysis@stainless steel and@graphite anode respectively.It is observed that the current efficiency of stainless steel anodic cell was higher than the graphite anodic cell.Therefore,steam splitting with the help of molten salts has shown an encouraging alternate to current methodology for H2 fuel production.展开更多
The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen gas.The gas composition and stable isotope characteristics vary significantl...The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen gas.The gas composition and stable isotope characteristics vary significantly,but the origin analysis of different gas types has previously been weak.Based on the geochemical parameters of gas samples from different depths and the analysis of geological settings,this research covers the diverse origins of natural gas in different strata.The gas components are mainly methane with a small amount of C_(2+),and non-hydrocarbon gases,including nitrogen(N_(2)),hydrogen(H_(2)),carbon dioxide(CO_(2)),and helium(He).At greater depth,the carbon isotope of methane becomes heavier,and the hydrogen isotope points to a lacustrine sedimentary environment.With increasing depth,the origins of N_(2)and CO_(2)change gradually from a mixture of organic and inorganic to inorganic.The origins of hydrogen gas are complex and include organic sources,water radiolysis,water-rock(Fe^(2+)-containing minerals)reactions,and mantle-derived.The shales of Denglouku and Shahezi Formations,as source rocks,provide the premise for generation and occurrence of organic gas.Furthermore,the deep faults and fluid activities in Basement Formation control the generation and migration of mantle-derived gas.The discovery of a high content of H_(2)in study area not only reveals the organic and inorganic association of natural-gas generation,but also provides a scientific basis for the exploration of deep hydrogen-rich gas.展开更多
Metal–organic frameworks(MOFs)are highly promising porous materials known for their exceptional porosity,extensive surface area,and customizable pore structures,making them an ideal solution for hydrogen storage.Howe...Metal–organic frameworks(MOFs)are highly promising porous materials known for their exceptional porosity,extensive surface area,and customizable pore structures,making them an ideal solution for hydrogen storage.However,most MOFs research remains confined to the laboratory,lacking practical applications.To address this,the author proposes a shift towards practical applications,the creation of a comprehensive MOFs database,alignment of synthesis with practical considerations,and diversification of MOFs applications.These steps are crucial for harnessing the full potential of MOFs in real-world energy challenges.展开更多
Hydrogen gas accelerates hydrocarbon generation, but little is known about its distribution and origin in petroliferous basins, which has hindered the further exploration.Taken the Jiyang Depression in eastern China a...Hydrogen gas accelerates hydrocarbon generation, but little is known about its distribution and origin in petroliferous basins, which has hindered the further exploration.Taken the Jiyang Depression in eastern China as an example, this study collected natural gas from different tectonic units, and analyzed various geochemical characters including gas contents, and carbon and hydrogen isotopic composition.The result shows that:(1) hydrogen gas is widespread distributed, but its content is very low, which typically ranges from 0.01% to 0.1% in this region;(2) the ratios of H2/3He, indicative of the origins of hydrogen gas, suggest that mantle-derived hydrogen is dominant.Even in tectonically stable areas absent with deep fluid activities, there is also mantle-derived;(3) the isotopic composition of hydrogen falls in the range of –798‰ to –628‰(relative to VSMOW standard).In areas with deep-derived fluids, the hydrogen gas has a similar isotopic composition with the previously documented deep-sourced gas, with lighter isotopic composition.In contrast, hydrogen gas has a heavier isotopic composition in relatively stable areas.The isotopic signatures suggest that there is a mixture of mantle- and crust-derived hydrogen gas in the relatively stable area, which is consistent with the H2/3He ratios.Therefore, it is clear that the hydrogen gas has a much wider distribution than found in the deep-derived fluid area, resulting in a much broader area with hydrogenating effect for resource rock.This understanding will provide new insights for hydrocarbon generation research and resource assessment in petroliferous basins.展开更多
The mass flow rate measurement using a critical nozzle shows the validity of the inviscid theory, indicating that the discharge coefficient increases and approaches unity as the Reynolds number increases under the ide...The mass flow rate measurement using a critical nozzle shows the validity of the inviscid theory, indicating that the discharge coefficient increases and approaches unity as the Reynolds number increases under the ideal gas law However, when the critical nozzle measures the mass flow rate of a real gas such as hydrogen at a pressure of hundreds bar, the discharge coefficient exceeds unity, and the real gas effects should be taken into account. The present study aims at investigating the flow features of the critical nozzle using high-pressured hydrogen gas. The axisymmetric, compressible Navier-Stokes computation is employed to simulate the critical nozzle flow, and a fully implicit finite volume method is used to discretize the governing equation system. The real gas effects are simulated to consider the intermolecular forces, which account for the possibility of liquefying hydrogen gas. The computational results are compared with past experimental data. It has been found that the coefficient of discharge for real gas can be corrected properly below unity adopting the real gas assumption.展开更多
Preferably 20 ppm anhydrous ammonia (NH<sub>3</sub>) is proposed to be added to hydrogen fuel (H) made from renewable energy sources (green hydrogen), so that H leaks may be easily detectable by smell, but...Preferably 20 ppm anhydrous ammonia (NH<sub>3</sub>) is proposed to be added to hydrogen fuel (H) made from renewable energy sources (green hydrogen), so that H leaks may be easily detectable by smell, but not dangerously toxic. Including this odor agent, would allow H to be distributed safely in pipes, as required by law, and it would allow H to be safely stored, transported, and exported for sale, and widely commercialized. Further research is suggested to identify optimum pressure, temperature, and automated technique for injecting NH<sub>3</sub> into H, and to chart the minimum concentration needed, as a function of temperature and humidity. An application to make hypersonic H burning aircraft safer for ground maintenance crews is proposed. An ability to make, store and distribute H, made from local sources of renewable energy, would reduce a need for fossil fuels, especially in poor, remote communities, where it could improve their economy by creating an export product for sale, while reducing pollution.展开更多
Electroactive anticorrosion coatings are specialized surface treatments that prevent or minimize corrosion. Thestudy employs strategic thermodynamic equilibriumcalculations to pioneer a novel factor in corrosion prote...Electroactive anticorrosion coatings are specialized surface treatments that prevent or minimize corrosion. Thestudy employs strategic thermodynamic equilibriumcalculations to pioneer a novel factor in corrosion protection.A first-time proposal, the total acidity (TA) potential of the hydrogen (pH) concept significantly shapes medicalmagnesium alloys. These coatings are meticulously designed for robust corrosion resistance, blending theoreticalinsights and practical applications to enhance our grasp of corrosion prevention mechanisms and establisha systematic approach to coating design. The groundbreaking significance of this study lies in its innovativeintegration of the TA/pH concept,which encompasses the TA/pH ratio of the chemical environment. This approachsurpasses convention by acknowledging the intricate interplay between the acidity and pH levels within thecoating formulation, thereby optimizing metal-phosphate-based conversion coatings and transforming corrosionmitigation strategies. To authenticate the TA/pH concept, the study comprehensively compares its findings withexisting research, rigorously validating the theoretical framework and reinforcing the correlates among TA/pHvalues and observed corrosion resistance in the coatings. The influence of mutations that occur naturally inthe detergent solution on persistent phosphorus changes is shown by empirical confirmation, which improvescorrosion resistance. This realization advances the field ofmaterials and the field’s knowledge of coated generation,particularly anticorrosion converter layers.展开更多
BACKGROUND Persistent vegetative state(PVS)is a devastating and long-lasting clinical condition with high morbidity and mortality;currently,there are no available effective interventions.CASE SUMMARY We report the cas...BACKGROUND Persistent vegetative state(PVS)is a devastating and long-lasting clinical condition with high morbidity and mortality;currently,there are no available effective interventions.CASE SUMMARY We report the case of an 11-year-old boy with PVS caused by severe intracerebral bleeding in the left hemisphere following anticoagulation treatment.The patient’s PVS severity showed no notable improvement after 2-mo neuroprotective treatment and rehabilitation,including nerve growth factor and baclofen,hyperbaric oxygen,and comprehensive bedside rehabilitation therapies.Daily inhalation treatment(4-6 h)of high-concentration hydrogen(H2)gas(66.6%H2+33.3%O2)was provided.Surprisingly,the patient’s orientation,consciousness,ability to speak,facial expressions,and locomotor function were significantly restored,along with improvements in essential general health status,after H2 gas inhalation treatment,which was consistent with stabilized neuropathology in the left hemisphere and increased Hounsfield unit values of computed tomography in the right hemisphere.The patient finally recovered to a near normal conscious state with a Coma Recovery Scale-Revised Score of 22 from his previous score of 3.CONCLUSION Phase 1 clinical trials are needed to explore the safety and efficacy of H2 gas inhalation in patients with PVS.展开更多
Magnesium is generally known to degrade in aqueous environments by an electrochemical reaction.The corrosion products of magnesium include hydrogen gas,Mg^(2+),and Mg(OH)_(2).Here,we summarize the published literature...Magnesium is generally known to degrade in aqueous environments by an electrochemical reaction.The corrosion products of magnesium include hydrogen gas,Mg^(2+),and Mg(OH)_(2).Here,we summarize the published literature describing the corrosion characteristics of magnesium,and the antitumor properties of magnesium-associated corrosion products,aiming to induce the therapeutic properties of magnesium and magnesium alloys in solid tumors.The therapeutic potential of corrosion products of magnesium is enormous.Hydrogen gas exhibits antioxidant and anti-inflammatory properties,which amount to potential anti-tumor characteristics.Mg(OH)_(2),which creates a localized alkaline microenvironment,represents a second approach for anti-tumor therapy with magnesium metal.Upregulated concentrations of Mg^(2+)ions in the local tumor microenvironment remodelling are considered a third approach for anti-tumor therapy.Therefore,we speculate about the different physical forms of magnesium that could create an anti-tumor microenvironment upon tumor interventional therapy,a technique that precisely places anti-tumor implants like particles and stents.Finally,we present our viewpoints on the potential use of magnesium in diverse solid tumor therapies to inhibit tumor progression.展开更多
Recently ionic liquids(ILs) are introduced as novel dual function gas hydrate inhibitors. However, no desired gas hydrate inhibition has been reported due to poor IL selection and/or tuning method. Trial & error a...Recently ionic liquids(ILs) are introduced as novel dual function gas hydrate inhibitors. However, no desired gas hydrate inhibition has been reported due to poor IL selection and/or tuning method. Trial & error as well as selection based on existing literature are the methods currently employed for selecting and/or tuning ILs. These methods are probabilistic, time consuming, expensive and may not result in selecting high performance ILs for gas hydrate mitigation. In this work, COSMO-RS is considered as a prescreening tool of ILs for gas hydrate mitigation by predicting the hydrogen bonding energies(E_(HB)) of studied IL inhibitors and comparing the predicted E_(HB) to the depression temperature(?) and induction time. Results show that, predicted EHBand chain length of ILs strongly relate and significantly affect the gas hydrate inhibition depression temperature but correlate moderately(R = 0.70) with average induction time in literature. It is deduced from the results that, ? increases with increasing IL EHBand/or decreases with increasing chain length. However, the cation–anion pairing of ILs also affects IL gas hydrate inhibition performance. Furthermore, a visual and better understanding of IL/water behavior for gas hydrate inhibition in terms of hydrogen bond donor and acceptor interaction analysis is also presented by determining the sigma profile and sigma potential of studied IL cations and anions used for gas hydrate mitigation for easy IL selection.展开更多
Thermal decomposition of formic acid on SiO2, CeO2 and γ-Al2O3 was studied as an elementary step of reverse water–gas shit reaction(RWGS) over supported Au catalysts. γ-Al2O3 showed the highest CO selectivity amo...Thermal decomposition of formic acid on SiO2, CeO2 and γ-Al2O3 was studied as an elementary step of reverse water–gas shit reaction(RWGS) over supported Au catalysts. γ-Al2O3 showed the highest CO selectivity among the tested oxides in the decomposition of formic acid. Infrared spectroscopy showed the formation of four formate species on γ-Al2O3: three η~1-type and one μ~2-type species, and these formates decomposed to CO at 473 K or higher. Au-loaded γ-Al2O3 samples were prepared by a depositionprecipitation method and used as catalysts for RWGS. The supported Au catalyst gave CO with high selectivity over 99% from CO2 and H2, which is attributed to the formation of formates on Au and subsequent decomposition to CO on γ-Al2O3.展开更多
Radiation damage can cause a series of gastrointestinal(GI)tract diseases.The development of safe and effective GI tract radioprotectants still remains a great challenge clinically.Here,we firstly report an oral radio...Radiation damage can cause a series of gastrointestinal(GI)tract diseases.The development of safe and effective GI tract radioprotectants still remains a great challenge clinically.Here,we firstly report an oral radioprotectant Gel@GYY that integrates a porous gelatin-based(Gel)hydrogel and a pH-responsive hydrogen sulfide(H2S)donor GYY4137(morpholin-4-ium 4 methoxyphenyl(morpholino)phosphinodithioate).Gel@GYY has a remarkable adhesion ability and long retention time,which not only enables responsive release of low-dose H2S in stomach and subsequently sustained release of H2S in the whole intestinal tract especially in the colon,but also ensures a close contact between H2S and GI tract.The released H2S can effectively scavenge free radicals induced by X-ray radiation,reduce lipid peroxidation level,repair DNA damage and recover vital superoxide dismutase and glutathione peroxidase activities.Meanwhile,the released H2S inhibits radiation-induced activation of nuclear factorκB(NF-κB),thus reducing inflammatory cytokines levels in GI tract.After treatment,Gel@GYY displays efficient excretion from mice body due to its biodegradability.This work provides a new insight for therapeutic application of intelligent H2S-releasing oral delivery system and potential alternative to clinical GI physical damage protectant.展开更多
The improvement of hydrogen storage materials is a key issue for storage and delivery of hydrogen energy before its potential can be realized. As hydrogen storage media, rare-earth hydrogen storage materials have been...The improvement of hydrogen storage materials is a key issue for storage and delivery of hydrogen energy before its potential can be realized. As hydrogen storage media, rare-earth hydrogen storage materials have been systematically studied in order to improve storage capacity, kinetics, thermodynamics and electrochemical performance. In this review, we focus on recent research progress of gaseous sorption and electrochemical hydrogen storage properties of rare-earth alloys and highlight their commercial applications including hydrogen storage tanks and nickel metal hydride batteries. Furthermore, development trend and prospective of rare-earth hydrogen storage materials are discussed.展开更多
Combined with the use of renewable energy sources for its production,hydrogen represents a possible alternative gas turbine fuel within future low emission power generation.Due to the large difference in the physical ...Combined with the use of renewable energy sources for its production,hydrogen represents a possible alternative gas turbine fuel within future low emission power generation.Due to the large difference in the physical properties of hydrogen compared to other fuels such as natural gas,well established gas turbine combustion systems cannot be directly applied for dry-low-NO_(x)(DLN)hydrogen combustion.Thus,the development of DLN combustion technologies is an essential and challenging task for the future of hydrogen fuelled gas turbines.The DLN micromix combustion principle for hydrogen fuel has been developed to significantly reduce NO_(x) emissions.This combustion principle is based on cross-flow mixing of air and gaseous hydrogen which reacts in multiple miniaturized diffusion-type flames.The major advantages of this combustion principle are the inherent safety against flash-back and the low NO_(x) emissions due to a very short residence time of reactants in the flame region of the micro-flames.The micromix combustion technology has been already proven experimentally and numerically for pure hydrogen fuel operation at different energy density levels.The aim of the present study is to apply and compare different combustion models for the characterization of the micromix flame structure,its interaction with the flow field and its NO_(x) emissions.The study reveals great potential for the successful application of numerical flow simulation to predict flame structure and NO_(x) emission level of micromix hydrogen combustion,help understanding the flow phenomena related with the micromixing,reaction zone and NO_(x) formation and support further optimization of the burner performance.展开更多
In this study,various chemical treatments were performed on clay-rich media to investigate their effects on hydrogen adsorption performance.We unequivocally demonstrated that acid-treated samples exhibited signifi-can...In this study,various chemical treatments were performed on clay-rich media to investigate their effects on hydrogen adsorption performance.We unequivocally demonstrated that acid-treated samples exhibited signifi-cant structural changes compared with those treated with alkali solutions.Gas adsorption isotherms and powder X-ray diffraction analyses clearly revealed that the acid treatment of clayey materials not only increased their surface area,but also enhanced hydrogen sorption uptake,increased interstratification,and reduced particle size.Most importantly,we succeeded in rationalizing the improvement in hydrogen uptake by sequentially applying purification,followed by acid treatment.展开更多
Decarbonization of energy economy is nowadays a topical theme,and several pathways are under discussion.Gaseous fuels have a fundamental role for this transition,and the production of low carbon-impact fuels is necess...Decarbonization of energy economy is nowadays a topical theme,and several pathways are under discussion.Gaseous fuels have a fundamental role for this transition,and the production of low carbon-impact fuels is necessary to deal with this challenge.The generation of renewable hydrogen is a trusted solution since this energy vector can be promptly produced from electricity and injected into the existing natural gas infrastructure,granting storage capacity and easy transportation.This scenario will lead,in the near future,to hydrogen enrichment of natural gas,whose impact on the infrastructures is being actively studied.The effect on end-user devices such as domestic gas boilers,instead,is still little analyzed and tested,but is fundamental to be assessed.The aim of this research is to generate knowledge on the effect of hydrogen enrichment on the widely used premixed boilers:the investigations include pollutant emissions,efficiency,flashback and explosion hazard,control system and materials selection.A model for calculating several parameters related to combustion of hydrogen enriched natural gas is presented.Guidelines for the design of new components are provided,and an insight is given on the maximum hydrogen blending bearable by the current boilers.展开更多
文摘AIM: To study the effect of H2 gas on liver injury in massive hepatectomy using the Intermittent Pringle maneuver in swine. METHODS: Male Bama pigs (n = 14) treated with ketamine hydrochloride and Sumianxin Ⅱ as induc- tion drugs followed by inhalation anesthesia with 2% isoflurane, underwent 70% hepatotectomy with loss of bleeding less than 50 mL, and with hepatic pedicle occlusion for 20 min, were divided into two groups: Hydrogen-group (n = 7), the pigs with inhalation of 2% hydrogen by the tracheal intubation during major hepa- totectomy; Contrast-group (n= 7), underwent 70% hepatotectomy without inhalation of hydrogen. Hemo- dynamic changes and plasma concentrations of alanine aminotransferase (ALT), aspartate aminotransferase (AST), hyaluronic acid (HA), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and malondialdehyde (MDA) in liver tissue were measured at pre-operation, post-hepatotectomy (PH) 1 h and 3 h. The apoptosis and proliferating cell nuclear antigen (PCNA) expres- sion in liver remnant were evaluated at PH 3 h. Then we compared the two groups by these marks to evalu- ate the effect of the hydrogen in the liver injury during major hepatotectomy with the Pringle Maneuver in the swine. RESULTS: There were no significant differences in body weight, blood loss and removal liver weight be- tween the two groups. There was no significant differ- ence in changes of portal vein pressure between two groups at pre-operation, PH 30 min, but in hydrogen gas treated-group it slightly decrease and lower than its in Contrast-group at PH 3 h, although there were no significant difference (P = 0.655). ALT and AST in Hydrogen-group was significantly lower comparing to Contrast-group (P = 0.036, P = 0.011, vs P = 0.032, P = 0.013) at PH 1 h and 3 h, although the two groups all increased. The MDA level increased between the two group at PH i h and 3 h. In the hydrogen gas treated- group, the MDA level was not significantly significant at pre-operation and significantly low at PH 1 h and 3 h comparing to Contrast-group (P = 0.0005, P = 0.0004). In Hydrogen-group, the HA level was also significantly low to Contrast-group (P = 0.0005, P = 0.0005) al- though the two groups all increased at PH 1 h and 3 h. The expression of cluster of differentiation molecule 31 molecules Hydrogen-group was low to Contrast-group. However, PCNA index (%) was not statistically signifi- cant between the two groups (P = 0.802). Micropho- tometric evaluation of apoptotic index (AI) in terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling-stained tissue after hepatotectomy for 3h, the AI% level in the hydrogen was significantly low to Contrast-group (P = 0.012). There were no significant difference between Hydrogen-group and Contrast- group at pre-operation (P = 0.653, P = 0.423), but after massive hepatotectomy, the TNF-α and IL-6 levels increase, and its in Hydrogen-group was significantly low compared with Contrast-group (P = 0.022, P = 0.013, vs P = 0.016, P= 0.012), respectively. Hydro- gen-gas inhalation reduce levels of these markers and relieved morphological liver injury and apoptosis.CONCLUSION: H2 gas attenuates markedly ischemia and portal hyperperfusion injury in pigs with massive hepatotectomy, possibly by the reduction of inflamma- tion and oxidative stress, maybe a potential agent for treatment in clinic.
基金Project supported by National Natural Science Foundatron of China( Grant No.59895157), and Science Foundation of Shanghai Municipal Commission of Science and Technology (Grant No. 02ZE14033 )
文摘The fracture behavior of disordered and ordered Ni4Mo alloy was investigated by tensile tests in hydrogen gas or during hydrogen charging. The results show that the ductility of the disordered alloy decreased slightly with the hydrogen pressure increasing, while that of the ordered alloy decreased rapidly with the hydrogen pressure increasing. However, the ductility of both disordered and ordered alloys reduced similarly seriously with the charging current density increasing. Therefore, the mechanism of order-induced embrittlement of Ni4 Mo alloy in hydrogen gas is supposed to be that atomic order accelerates the kinetics of the catalytic reaction for the dissociation of molecular H2 into atomic H.
基金supported by e-Sciencefund(13-02-03-3093)Postgraduate Research Grant(PPP)(PG027-2013B)+4 种基金FRGS(FP038-2014B)MOHE-ERGS(ER002-2013A)funding from UMRG(RP007B-13AFR)High Impact Research Program(UM.C/625/1/HIR/079)HIR-MOHE(UM.C/625/1/HIR/MOHE/SC/06)
文摘Current study reports a rapid one-pot non-hydrolytic condition in the synthesis of Sn O2QDs nanopowder using tin(II) stearate(Sn(St)2) as environmentally-benign organometallic precursor,which is an unprecedentedly employed-compound in preceding Sn O2nanopowder productions.The as-synthesized Sn O2QDs that are hydrophobic can be easily transferred from organic solvent to aqueous solution through a robust ligand exchange method.The stearate-capping ligands on the surface of QDs can be replaced by beta-cyclodextrin(β-CD) and eventually render the QDs highly water soluble,which ultimately make it exhibit bi-functionality for different liquid medium applications.Structural characterizations reveal that the bi-functional QDs are indeed well-matched with the standard rutile Sn O2cassiterite phase without the presence of any impurities.The QDs can be interchangeably used as photocatalyst for both aqueous and non-aqueous phase,where it shows significant enhancement of hydrogen gas production as compared to that of commercial Sn O2nanopowder.
基金Projected supported by the HEC of Pakistan for international initiative research support programme (IRSIP).
文摘Zinc oxide (ZnO) nanorods are prepared using equimolar solution of zinc nitrate ((Zn(NO3)2) and hexamethylenete- tramine (C6HleN4) by the hydrothermal technique at 80 ~C for 12 h. Epitaxial growth is explored by X-ray diffraction (XRD) patterns, revealing that the ZnO nanorods have a hexagonal (wurtzite) structure. Absorption spectra of ZnO are measured by UV-visible spectrometer. The surface morphology is investigated by field emission scanning electron mi- croscopy (FESEM). The synthesized ZnO nanorods are used for detecting the 150 ~C hydrogen gas with a concentration over 1000 ppm. The obtained results show a reversible response. The influence of operating temperature on hydrogen gas detecting characteristic of ZnO nanorods is also investigated.
基金the financial supports from the EPSRC (EP/J000582/1 and EP/F026412/1)Ningbo Municipal People’s Government (3315 Plan and 2014A35001-1)。
文摘This study deals with the optimization of best working conditions in molten melt for the production of hydrogen(H2) gas.Limited research has been carried out on how electrochemical process occurs through steam splitting via molten hydroxide.54 combinations of cathode,anode,temperature and voltage have been investigated for the optimization of best working conditions with molten hydroxide for hydrogen gas production.All these electrochemical investigations were carried out at 225 to 300℃ temperature and 1.5 to 2.5 V applied voltage values.The current efficiency of 90.5,80.0 and 68.6% has been achieved using stainless steel anodic cell with nickel,stainless steel and platinum working cathode respectively.For nickel cathode,an increase in the current directly affected the hydrogen gas flow rate at cathode.It can be hypothesized from the noted results that increase in current is directly proportional to operating temperature and applied voltage.Higher values were noted when the applied voltages increased from 1.5 to 2.5 V at 300℃,the flow rate of hydrogen gas increased from 1.5 to 11.3 cm^(3) min^(-1),1.0 to 13 cm^(3) min^(-1) in case of electrolysis@stainless steel and@graphite anode respectively.It is observed that the current efficiency of stainless steel anodic cell was higher than the graphite anodic cell.Therefore,steam splitting with the help of molten salts has shown an encouraging alternate to current methodology for H2 fuel production.
基金supported by the National Natural Science Foundation of China(Grant No.42072168)the National Key R&D Program of China(Grant No.2019YFC0605405)the Fundamental Research Funds for the Central Universities(Grant No.2023ZKPYDC07)。
文摘The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen gas.The gas composition and stable isotope characteristics vary significantly,but the origin analysis of different gas types has previously been weak.Based on the geochemical parameters of gas samples from different depths and the analysis of geological settings,this research covers the diverse origins of natural gas in different strata.The gas components are mainly methane with a small amount of C_(2+),and non-hydrocarbon gases,including nitrogen(N_(2)),hydrogen(H_(2)),carbon dioxide(CO_(2)),and helium(He).At greater depth,the carbon isotope of methane becomes heavier,and the hydrogen isotope points to a lacustrine sedimentary environment.With increasing depth,the origins of N_(2)and CO_(2)change gradually from a mixture of organic and inorganic to inorganic.The origins of hydrogen gas are complex and include organic sources,water radiolysis,water-rock(Fe^(2+)-containing minerals)reactions,and mantle-derived.The shales of Denglouku and Shahezi Formations,as source rocks,provide the premise for generation and occurrence of organic gas.Furthermore,the deep faults and fluid activities in Basement Formation control the generation and migration of mantle-derived gas.The discovery of a high content of H_(2)in study area not only reveals the organic and inorganic association of natural-gas generation,but also provides a scientific basis for the exploration of deep hydrogen-rich gas.
基金supported by the National Natural Science Foundation of China(52270027,52170037,and U20A20322)the Science and Technology Program of Jilin Province(20210201066GX)+1 种基金Scientific research project of Ecological Environment Department of Jilin Province(2023-05)Jilin Provincial Science and Technology Department Science and Technology Innovation and Entrepreneurship outstanding talent program for young and middle-aged(20230508051RC).
文摘Metal–organic frameworks(MOFs)are highly promising porous materials known for their exceptional porosity,extensive surface area,and customizable pore structures,making them an ideal solution for hydrogen storage.However,most MOFs research remains confined to the laboratory,lacking practical applications.To address this,the author proposes a shift towards practical applications,the creation of a comprehensive MOFs database,alignment of synthesis with practical considerations,and diversification of MOFs applications.These steps are crucial for harnessing the full potential of MOFs in real-world energy challenges.
基金funded by the National Natural Science Foundation of China (Grant Nos.:41102075 and 41230312)the Open Fund of Key Laboratory of Tectonics and Petroleum Resources (China University of Geosciences), Ministry of Education (Grant No.: TPR-2012-24)
文摘Hydrogen gas accelerates hydrocarbon generation, but little is known about its distribution and origin in petroliferous basins, which has hindered the further exploration.Taken the Jiyang Depression in eastern China as an example, this study collected natural gas from different tectonic units, and analyzed various geochemical characters including gas contents, and carbon and hydrogen isotopic composition.The result shows that:(1) hydrogen gas is widespread distributed, but its content is very low, which typically ranges from 0.01% to 0.1% in this region;(2) the ratios of H2/3He, indicative of the origins of hydrogen gas, suggest that mantle-derived hydrogen is dominant.Even in tectonically stable areas absent with deep fluid activities, there is also mantle-derived;(3) the isotopic composition of hydrogen falls in the range of –798‰ to –628‰(relative to VSMOW standard).In areas with deep-derived fluids, the hydrogen gas has a similar isotopic composition with the previously documented deep-sourced gas, with lighter isotopic composition.In contrast, hydrogen gas has a heavier isotopic composition in relatively stable areas.The isotopic signatures suggest that there is a mixture of mantle- and crust-derived hydrogen gas in the relatively stable area, which is consistent with the H2/3He ratios.Therefore, it is clear that the hydrogen gas has a much wider distribution than found in the deep-derived fluid area, resulting in a much broader area with hydrogenating effect for resource rock.This understanding will provide new insights for hydrocarbon generation research and resource assessment in petroliferous basins.
文摘The mass flow rate measurement using a critical nozzle shows the validity of the inviscid theory, indicating that the discharge coefficient increases and approaches unity as the Reynolds number increases under the ideal gas law However, when the critical nozzle measures the mass flow rate of a real gas such as hydrogen at a pressure of hundreds bar, the discharge coefficient exceeds unity, and the real gas effects should be taken into account. The present study aims at investigating the flow features of the critical nozzle using high-pressured hydrogen gas. The axisymmetric, compressible Navier-Stokes computation is employed to simulate the critical nozzle flow, and a fully implicit finite volume method is used to discretize the governing equation system. The real gas effects are simulated to consider the intermolecular forces, which account for the possibility of liquefying hydrogen gas. The computational results are compared with past experimental data. It has been found that the coefficient of discharge for real gas can be corrected properly below unity adopting the real gas assumption.
文摘Preferably 20 ppm anhydrous ammonia (NH<sub>3</sub>) is proposed to be added to hydrogen fuel (H) made from renewable energy sources (green hydrogen), so that H leaks may be easily detectable by smell, but not dangerously toxic. Including this odor agent, would allow H to be distributed safely in pipes, as required by law, and it would allow H to be safely stored, transported, and exported for sale, and widely commercialized. Further research is suggested to identify optimum pressure, temperature, and automated technique for injecting NH<sub>3</sub> into H, and to chart the minimum concentration needed, as a function of temperature and humidity. An application to make hypersonic H burning aircraft safer for ground maintenance crews is proposed. An ability to make, store and distribute H, made from local sources of renewable energy, would reduce a need for fossil fuels, especially in poor, remote communities, where it could improve their economy by creating an export product for sale, while reducing pollution.
基金the below mentioned organisation:Key Research and Development Special Project of Henan Provincial Science and Technology(222102230025)Key Research and Development Special Project of Henan Provincial Science and Technology(232102231015)+2 种基金Key Research and Development Special Project of Henan Provincial Science and Technology(232102231011)Natural Science Foundation of Henan Province(No.004053100)Major Science Research Project of High Education of Henan Province(No.23B430016).
文摘Electroactive anticorrosion coatings are specialized surface treatments that prevent or minimize corrosion. Thestudy employs strategic thermodynamic equilibriumcalculations to pioneer a novel factor in corrosion protection.A first-time proposal, the total acidity (TA) potential of the hydrogen (pH) concept significantly shapes medicalmagnesium alloys. These coatings are meticulously designed for robust corrosion resistance, blending theoreticalinsights and practical applications to enhance our grasp of corrosion prevention mechanisms and establisha systematic approach to coating design. The groundbreaking significance of this study lies in its innovativeintegration of the TA/pH concept,which encompasses the TA/pH ratio of the chemical environment. This approachsurpasses convention by acknowledging the intricate interplay between the acidity and pH levels within thecoating formulation, thereby optimizing metal-phosphate-based conversion coatings and transforming corrosionmitigation strategies. To authenticate the TA/pH concept, the study comprehensively compares its findings withexisting research, rigorously validating the theoretical framework and reinforcing the correlates among TA/pHvalues and observed corrosion resistance in the coatings. The influence of mutations that occur naturally inthe detergent solution on persistent phosphorus changes is shown by empirical confirmation, which improvescorrosion resistance. This realization advances the field ofmaterials and the field’s knowledge of coated generation,particularly anticorrosion converter layers.
文摘BACKGROUND Persistent vegetative state(PVS)is a devastating and long-lasting clinical condition with high morbidity and mortality;currently,there are no available effective interventions.CASE SUMMARY We report the case of an 11-year-old boy with PVS caused by severe intracerebral bleeding in the left hemisphere following anticoagulation treatment.The patient’s PVS severity showed no notable improvement after 2-mo neuroprotective treatment and rehabilitation,including nerve growth factor and baclofen,hyperbaric oxygen,and comprehensive bedside rehabilitation therapies.Daily inhalation treatment(4-6 h)of high-concentration hydrogen(H2)gas(66.6%H2+33.3%O2)was provided.Surprisingly,the patient’s orientation,consciousness,ability to speak,facial expressions,and locomotor function were significantly restored,along with improvements in essential general health status,after H2 gas inhalation treatment,which was consistent with stabilized neuropathology in the left hemisphere and increased Hounsfield unit values of computed tomography in the right hemisphere.The patient finally recovered to a near normal conscious state with a Coma Recovery Scale-Revised Score of 22 from his previous score of 3.CONCLUSION Phase 1 clinical trials are needed to explore the safety and efficacy of H2 gas inhalation in patients with PVS.
基金supported by the Open Funds for Shaanxi Provincial Key Laboratory of Infection and Immune Diseases(2022-KFZD-1)Natural Science Basic Research Program of Shaanxi(2021JM-080,2022JQ-832)the National Natural Science Foundation of China(82203047)
文摘Magnesium is generally known to degrade in aqueous environments by an electrochemical reaction.The corrosion products of magnesium include hydrogen gas,Mg^(2+),and Mg(OH)_(2).Here,we summarize the published literature describing the corrosion characteristics of magnesium,and the antitumor properties of magnesium-associated corrosion products,aiming to induce the therapeutic properties of magnesium and magnesium alloys in solid tumors.The therapeutic potential of corrosion products of magnesium is enormous.Hydrogen gas exhibits antioxidant and anti-inflammatory properties,which amount to potential anti-tumor characteristics.Mg(OH)_(2),which creates a localized alkaline microenvironment,represents a second approach for anti-tumor therapy with magnesium metal.Upregulated concentrations of Mg^(2+)ions in the local tumor microenvironment remodelling are considered a third approach for anti-tumor therapy.Therefore,we speculate about the different physical forms of magnesium that could create an anti-tumor microenvironment upon tumor interventional therapy,a technique that precisely places anti-tumor implants like particles and stents.Finally,we present our viewpoints on the potential use of magnesium in diverse solid tumor therapies to inhibit tumor progression.
文摘Recently ionic liquids(ILs) are introduced as novel dual function gas hydrate inhibitors. However, no desired gas hydrate inhibition has been reported due to poor IL selection and/or tuning method. Trial & error as well as selection based on existing literature are the methods currently employed for selecting and/or tuning ILs. These methods are probabilistic, time consuming, expensive and may not result in selecting high performance ILs for gas hydrate mitigation. In this work, COSMO-RS is considered as a prescreening tool of ILs for gas hydrate mitigation by predicting the hydrogen bonding energies(E_(HB)) of studied IL inhibitors and comparing the predicted E_(HB) to the depression temperature(?) and induction time. Results show that, predicted EHBand chain length of ILs strongly relate and significantly affect the gas hydrate inhibition depression temperature but correlate moderately(R = 0.70) with average induction time in literature. It is deduced from the results that, ? increases with increasing IL EHBand/or decreases with increasing chain length. However, the cation–anion pairing of ILs also affects IL gas hydrate inhibition performance. Furthermore, a visual and better understanding of IL/water behavior for gas hydrate inhibition in terms of hydrogen bond donor and acceptor interaction analysis is also presented by determining the sigma profile and sigma potential of studied IL cations and anions used for gas hydrate mitigation for easy IL selection.
文摘Thermal decomposition of formic acid on SiO2, CeO2 and γ-Al2O3 was studied as an elementary step of reverse water–gas shit reaction(RWGS) over supported Au catalysts. γ-Al2O3 showed the highest CO selectivity among the tested oxides in the decomposition of formic acid. Infrared spectroscopy showed the formation of four formate species on γ-Al2O3: three η~1-type and one μ~2-type species, and these formates decomposed to CO at 473 K or higher. Au-loaded γ-Al2O3 samples were prepared by a depositionprecipitation method and used as catalysts for RWGS. The supported Au catalyst gave CO with high selectivity over 99% from CO2 and H2, which is attributed to the formation of formates on Au and subsequent decomposition to CO on γ-Al2O3.
基金the National Natural Science Foundation of China(Nos.22175182,21471103)Sheng Yuan Cooperation(No.2021SYHZ0048)+1 种基金Beijing Natural Science Foundation(No.2202064)the directional institutionalized scientific research platform relies on Beijing Synchrotron Radiation Facility of Chinese Academy of Sciences.
文摘Radiation damage can cause a series of gastrointestinal(GI)tract diseases.The development of safe and effective GI tract radioprotectants still remains a great challenge clinically.Here,we firstly report an oral radioprotectant Gel@GYY that integrates a porous gelatin-based(Gel)hydrogel and a pH-responsive hydrogen sulfide(H2S)donor GYY4137(morpholin-4-ium 4 methoxyphenyl(morpholino)phosphinodithioate).Gel@GYY has a remarkable adhesion ability and long retention time,which not only enables responsive release of low-dose H2S in stomach and subsequently sustained release of H2S in the whole intestinal tract especially in the colon,but also ensures a close contact between H2S and GI tract.The released H2S can effectively scavenge free radicals induced by X-ray radiation,reduce lipid peroxidation level,repair DNA damage and recover vital superoxide dismutase and glutathione peroxidase activities.Meanwhile,the released H2S inhibits radiation-induced activation of nuclear factorκB(NF-κB),thus reducing inflammatory cytokines levels in GI tract.After treatment,Gel@GYY displays efficient excretion from mice body due to its biodegradability.This work provides a new insight for therapeutic application of intelligent H2S-releasing oral delivery system and potential alternative to clinical GI physical damage protectant.
基金supported by the National Natural Science Foundation of China(Grant No.21521092)the Major Scientific and Technological Developing Project of Changchun City(Grant No.17SS013)+1 种基金the Scientific and Technological Developing Project of Jilin Province(Grant No.20180201098GX)the Natural Science Foundation of Jiangsu Province(Grant No.BK20141174)
文摘The improvement of hydrogen storage materials is a key issue for storage and delivery of hydrogen energy before its potential can be realized. As hydrogen storage media, rare-earth hydrogen storage materials have been systematically studied in order to improve storage capacity, kinetics, thermodynamics and electrochemical performance. In this review, we focus on recent research progress of gaseous sorption and electrochemical hydrogen storage properties of rare-earth alloys and highlight their commercial applications including hydrogen storage tanks and nickel metal hydride batteries. Furthermore, development trend and prospective of rare-earth hydrogen storage materials are discussed.
文摘Combined with the use of renewable energy sources for its production,hydrogen represents a possible alternative gas turbine fuel within future low emission power generation.Due to the large difference in the physical properties of hydrogen compared to other fuels such as natural gas,well established gas turbine combustion systems cannot be directly applied for dry-low-NO_(x)(DLN)hydrogen combustion.Thus,the development of DLN combustion technologies is an essential and challenging task for the future of hydrogen fuelled gas turbines.The DLN micromix combustion principle for hydrogen fuel has been developed to significantly reduce NO_(x) emissions.This combustion principle is based on cross-flow mixing of air and gaseous hydrogen which reacts in multiple miniaturized diffusion-type flames.The major advantages of this combustion principle are the inherent safety against flash-back and the low NO_(x) emissions due to a very short residence time of reactants in the flame region of the micro-flames.The micromix combustion technology has been already proven experimentally and numerically for pure hydrogen fuel operation at different energy density levels.The aim of the present study is to apply and compare different combustion models for the characterization of the micromix flame structure,its interaction with the flow field and its NO_(x) emissions.The study reveals great potential for the successful application of numerical flow simulation to predict flame structure and NO_(x) emission level of micromix hydrogen combustion,help understanding the flow phenomena related with the micromixing,reaction zone and NO_(x) formation and support further optimization of the burner performance.
基金supported by the European joint pro-gram on radioactive waste management for financial support(Grant ID:847593)for the project titled Hydrogen(H 2)Uptake and Physisorp-tion Mechanism in Micro-and Nano-porous Systems Application to Clayrock-hosted Nuclear Waste Repositories.M.R.T acknowledges Uni-versitéGrenoble Alpes,Institut des Sciences de la Terre(ISTerre),and eurad for supporting a postdoctoral fellowship.
文摘In this study,various chemical treatments were performed on clay-rich media to investigate their effects on hydrogen adsorption performance.We unequivocally demonstrated that acid-treated samples exhibited signifi-cant structural changes compared with those treated with alkali solutions.Gas adsorption isotherms and powder X-ray diffraction analyses clearly revealed that the acid treatment of clayey materials not only increased their surface area,but also enhanced hydrogen sorption uptake,increased interstratification,and reduced particle size.Most importantly,we succeeded in rationalizing the improvement in hydrogen uptake by sequentially applying purification,followed by acid treatment.
文摘Decarbonization of energy economy is nowadays a topical theme,and several pathways are under discussion.Gaseous fuels have a fundamental role for this transition,and the production of low carbon-impact fuels is necessary to deal with this challenge.The generation of renewable hydrogen is a trusted solution since this energy vector can be promptly produced from electricity and injected into the existing natural gas infrastructure,granting storage capacity and easy transportation.This scenario will lead,in the near future,to hydrogen enrichment of natural gas,whose impact on the infrastructures is being actively studied.The effect on end-user devices such as domestic gas boilers,instead,is still little analyzed and tested,but is fundamental to be assessed.The aim of this research is to generate knowledge on the effect of hydrogen enrichment on the widely used premixed boilers:the investigations include pollutant emissions,efficiency,flashback and explosion hazard,control system and materials selection.A model for calculating several parameters related to combustion of hydrogen enriched natural gas is presented.Guidelines for the design of new components are provided,and an insight is given on the maximum hydrogen blending bearable by the current boilers.