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The Capture and Catalytic Conversion of CO_(2) by Dendritic Mesoporous Silica-Based Nanoparticles
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作者 Yabin Wang Liangzhu Huang +2 位作者 Songwei Li Chuntai Liu Hua He 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期126-151,共26页
Dendritic mesoporous silica nanoparticles own three-dimensional center-radial channels and hierarchical pores,which endows themselves with super-high specific surface area,extremely large pore volumes,especially acces... Dendritic mesoporous silica nanoparticles own three-dimensional center-radial channels and hierarchical pores,which endows themselves with super-high specific surface area,extremely large pore volumes,especially accessible internal spaces,and so forth.Dissimilar guest species(such as organic groups or metal nanoparticles)could be readily decorated onto the interfaces of the channels and pores,realizing the functionalization of dendritic mesoporous silica nanoparticles for targeted applications.As adsorbents and catalysts,dendritic mesoporous silica nanoparticles-based materials have experienced nonignorable development in CO_(2)capture and catalytic conversion.This comprehensive review provides a critical survey on this pregnant subject,summarizing the designed construction of novel dendritic mesoporous silica nanoparticles-based materials,the involved chemical reactions(such as CO_(2)methanation,dry reforming of CH_(4)),the value-added chemicals from CO_(2)(such as cyclic carbonates,2-oxazolidinones,quinazoline-2,4(1H,3H)-diones),and so on.The adsorptive and catalytic performances have been compared with traditional silica mesoporous materials(such as SBA-15 or MCM-41),and the corresponding reaction mechanisms have been thoroughly revealed.It is sincerely expected that the in-depth discussion could give materials scientists certain inspiration to design brand-new dendritic mesoporous silica nanoparticles-based materials with superior capabilities towards CO_(2)capture,utilization,and storage. 展开更多
关键词 catalytic conversion CO_(2)adsorption CO_(2)capture dendritic mesoporous silica nanoparticles
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Rod-like mesoporous silica nanoparticles facilitate oral drug delivery via enhanced permeation and retention effect in mucus
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作者 Wenjuan Liu Luyu Zhang +5 位作者 Zirong Dong Kaiheng Liu Haisheng He Yi Lu Wei Wu Jianping Qi 《Nano Research》 SCIE EI CSCD 2022年第10期9243-9252,共10页
The physiochemical characteristics of nanoparticles affect their in vitro and in vivo performance significantly,such as diameter,surface chemistry,and shape.This paper disclosed the effect of enhanced permeation and r... The physiochemical characteristics of nanoparticles affect their in vitro and in vivo performance significantly,such as diameter,surface chemistry,and shape.This paper disclosed the effect of enhanced permeation and retention(EPR)in mucus caused by nanoparticle shape on improving oral absorption.The spherical and rod-like mesoporous silica nanoparticles(MSNs)were used to evaluate shape effect of EPR in mucus.Fenofibrate was loaded in MSNs as model drug.The in vitro release of fenofibrate from MSNs was dependent on nanoparticle shapes,but faster than that of raw drug.The drug release slowed down with the increase of aspect ratio due to longer channels in rod-like MSNs with higher aspect ratio.However,in vivo study showed that the oral bioavailability of fenofibrate was the highest after loading in rod-like MSNs with aspect ratio of 5.The in vitro study of mechanisms revealed that superior mucus diffusion ability of rod-like MSNs with aspect ratio of 5 was conductive to higher bioavailability.Meanwhile,more rod-like MSNs with higher aspect ratio were able to diffuse into mucus and reside there compared to spherical and short counterparts,which demonstrated higher aspect ratio was beneficial to EPR effect of nanoparticles in mucus.This study provides significant implication in rational oral drug carrier design. 展开更多
关键词 mesoporous silica nanoparticles shape effect FENOFIBRATE mucus layer enhanced permeation and retention effect
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Highly Efficient Heavy-Metal-Ion Removal from Shellfish Processing Liquid with Low Protein and Polysaccharide Loss by Hybrid Mesoporous Silica Diol-APDC-SBA15 被引量:1
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作者 QI Yanxia SONG Yang +4 位作者 LIU Chang QI Shizhe WANG Haibo CAO Jijuan ZHAO Qiancheng 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第1期221-228,共8页
Heavy metal ions in shellfish products are harmful to human health,and their removal with low nutrient loss remains challenging.Herein,a new type of mesoporous silica(SBA15),modified internally with ammonium pyrrolidi... Heavy metal ions in shellfish products are harmful to human health,and their removal with low nutrient loss remains challenging.Herein,a new type of mesoporous silica(SBA15),modified internally with ammonium pyrrolidine dithiocarbamate(APDC)and externally with alkyl-diol groups,which was named as Diol-APDC-SBA15,was successfully developed and characterized by powder X-ray diffraction patterns,nitrogen adsorption,and Fourier transform infrared spectroscopy.The solutions with lead,chromium,cadmium,and copper were used to investigate the adsorption capacity of Diol-APDC-SBA15.Diol-APDC-SBA15 was adopted to remove heavy metals from cooking liquids of clams(Ruditapes philippinarum),hydrolysate liquids of oysters(Ostrea gigas Thunberg),and polysaccharide solution from the cooking liquid of R.philippinarum.The efficiencies of removing heavy metal ions and the loss rates of proteins and polysaccharides were examined.The results showed that the adsorption capacities of Diol-APDCSBA15 for Pb,Cr,Cd,and Cu in standard heavy-metal solutions were 161.4,166.1,29.6,and 60.2mgg^(−1),respectively.The removal efficiency of Diol-APDC-SBA15 for Pb in the three shellfish processing liquids ranged from 60.5%to 99.6%.The Cr removal efficiency was above 99.9%in the oyster hydrolysate liquid.Meanwhile,the percentages of polysaccharide loss were 5.5%and 3.7%in the cooking liquid of clam and polysaccharide solution,respectively,and the protein loss was 1.2%in the oyster hydrolysate liquid.Therefore,the Diol-APDC-SBA15 material exhibits a great potential application in the removal of heavy metals from shellfish processing liquids with low losses of proteins and polysaccharides. 展开更多
关键词 heavy-metal removal modified mesoporous silica shellfish processing liquid protein POLYSACCHARIDE
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Core-shell-embedded Mesoporous Silica Capsules for Atmospheric Water Harvesting
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作者 ZHANG Shangsheng XU Shuman +5 位作者 LEI Ruicheng PAN Yuliang MA Tao ZHANG Zheng LIU Chunsheng ZHANG Zengzhi 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第5期951-959,共9页
A one-step ultrasonic mechanical method was used to synthesize a kind of atmospheric water harvesting material with high water harvesting performance in a wide relative humidity(RH)range,especially at low RH(RH<40%... A one-step ultrasonic mechanical method was used to synthesize a kind of atmospheric water harvesting material with high water harvesting performance in a wide relative humidity(RH)range,especially at low RH(RH<40%),namely,mesoporous silica capsule(MSC)with core-shell structure.Transmission electron microscopy(TEM),nitrogen adsorption and other characterization techniques were used to study the formation process of nano-microspheres.A new mechanism of self-adaptive concentration gradient regulation of silicon migration and recombination core-shell structure was proposed to explain the formation of a cavity in the MSC system.The core-shell design can enhance the specific surface area and pore volume while maintaining the monodispersity and mesoporous size.To study the water harvesting performance of MSC,solid silica nanoparticles(SSN)and mesoporous silica nanoparticles(MSN)were prepared.In a small atmospheric water collection test(25℃,40%RH),the water vapour adsorption and desorption kinetics of MSC,SSN,MSN and a commercial silica gel(CSG)were compared and analyzed.The results show that the MSC with mesoporous channels and core-shell structure can provide about 0.324 gwater/gadsorbent,79%higher than the CSG(0.181 gwater/gadsorbent).It is 25.1%higher than that of 0.259 gwater/gadsorbentof un-hollowed MSN and 980%higher than that of0.03 gwater/gadsorbentof un-hollowed SSN.The material has a large specific surface area and pore volume,simple preparation method and low cost,which provides a feasible idea for realising atmospheric water collection in arid and semi-arid regions. 展开更多
关键词 mesoporous silica nanocapsules core-shell structure atmospheric water harvesting adsorption performance
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Mesoporous silica nanoparticles with chiral pattern topological structure function as“antiskid tires”on the intestinal mucosa to facilitate oral drugs delivery
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作者 Wei Xin Lin Wang +9 位作者 Jiahui Lin Yanbu Wang Qi pan Yang Han Zhiye Bao Shun Zong Ying Cheng Xuchun Chen Lin Zhao Heran Li 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2023年第2期106-123,共18页
The weak adhesion between nanocarriers and the intestinal mucosa was one of the main reasons caused the failure in oral delivery.Inspired by the“antiskid tires”with complex chiral patterns,mesoporous silica nanopart... The weak adhesion between nanocarriers and the intestinal mucosa was one of the main reasons caused the failure in oral delivery.Inspired by the“antiskid tires”with complex chiral patterns,mesoporous silica nanoparticles AT-R@CMSN exhibiting geometrical chiral structure were designed to improve the surface/interface roughness in nanoscale,and employed as the hosting system for insoluble drugs nimesulide(NMS)and ibuprofen(IBU).Once performing the delivery tasks,AT-R@CMSN with rigid skeleton protected the loaded drug and reduced the irritation of drug on gastrointestinal tract(GIT),while their porous structure deprived drug crystal and improved drug release.More importantly,AT-R@CMSN functioned as“antiskid tire”to produce higher friction on intestinal mucosa and substantively influencedmultiple biological processes,including“contact”,“adhesion”,“retention”,“permeation”and“uptake”,compared to the achiral S@MSN,thereby improving the oral adsorption effectiveness of such drug delivery systems.By engineering AT-R@CMSN to overcome the stability,solubility and permeability bottlenecks of drugs,orally administered NMS or IBU loaded AT-R@CMSN could achieve higher relative bioavailability(705.95%and 444.42%,respectively)and stronger anti-inflammation effect.In addition,AT-R@CMSN displayed favorable biocompatibility and biodegradability.Undoubtedly,the present finding helped to understand the oral adsorption process of nanocarriers,and provided novel insights into the rational design of nanocarriers. 展开更多
关键词 Chiral mesoporous silica Bio-adhesion Oral delivery Intestinal mucosa Nanocarrier design
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Effect of salvianolic acid B-loaded mesoporous silica nanoparticles on myocardial ischemia-reperfusion injury
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作者 Ming-Juan Yang Xiao-Ying Han +9 位作者 Ou Qiao Hai-Xia Ji Yi Zhang Xin-Yu Zhang Wen-Zhe Wang Xia Li Juan Wang Lan-Ping Guo Lu-Qi Huang Wen-Yuan Gao 《Traditional Medicine Research》 2023年第8期25-36,共12页
Background:Currently,no drugs can specifically improve clinical cardiac ischemia-reperfusion injury or the prognosis of hemodialysis.Salvianolic acid B(SalB)is a widely used cardiac protectant;however,its clinical app... Background:Currently,no drugs can specifically improve clinical cardiac ischemia-reperfusion injury or the prognosis of hemodialysis.Salvianolic acid B(SalB)is a widely used cardiac protectant;however,its clinical application is limited by its low oral bioavailability and poor intestinal absorption.The exploration of its preparation and clinical applications has become a research hotspot in recent years.Methods:To determine whether mesoporous silica nanoparticles(MSNs)efficiently delivered SalB to the heart and SalB@MSNs-RhB reduced myocardial ischemia-reperfusion injury,we constructed a myocardial ischemia-reperfusion male rat model,hypoxia/reoxygenation cardiomyocytes,and treated them with SalB@MSNs-RhB.Results:SalB@MSNs-RhB showed improved bioavailability,therapeutic effect,heightened JAK2/STAT3-dependent pro-survival signaling,and antioxidant responses,thereby protecting cardiomyocytes from ischemia-reperfusion injury-induced oxidative stress and apoptosis.Conclusion:This use of SalB-loaded nanoparticles and investigation of their mechanism of action may provide a new strategy for treating cardiomyocytes.Thus,hypoxia/reoxygenation promotes the clinical application of SalB. 展开更多
关键词 salvianolic acid B myocardial ischemia-reperfusion injury mesoporous silica NANOPARTICLES
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Fabrication and characterization of tungsten-containing mesoporous silica for heterogeneous oxidative desulfurization 被引量:7
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作者 张铭 朱文帅 +5 位作者 李宏平 荀苏杭 李猛 李亚男 魏延臣 李华明 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第6期971-978,共8页
A series of functional,tungsten-containing mesoporous silica materials(W-SiO2) have been fabricated directly from an ionic liquid that contained imidazole and polyoxometalate,which acted as mesoporous template and m... A series of functional,tungsten-containing mesoporous silica materials(W-SiO2) have been fabricated directly from an ionic liquid that contained imidazole and polyoxometalate,which acted as mesoporous template and metal source respectively.These materials were then characterized through X-ray diffraction(XRD),transmission electron microscopy(TEM),Raman spectroscopy,Fourier transform infrared spectra(FTIR),diffuse reflectance spectra(DRS),and N2 adsorption-desorption,which were found to contain tungsten species that were effectively dispersed throughout the structure.The as-prepared materials W-SiO2 were also found to possess a mesoporous structure.The pore diameters of the respective sample W-SiO2-20 determined from the TEM images ranged from 2 to 4 nm,which was close to the average pore size determined from the nitrogen desorption isotherm(2.9 nm).The materials were evaluated as catalysts for the heterogeneous oxidative desulfurization of dibenzothiophene(DBT),which is able to achieve deep desulfurization within 40 min under the optimal conditions(Catalyst(W-SiO2-20)= 0.01 g,temperature = 60℃,oxidant(H2O2)= 20 μL).For the removal of different organic sulfur compounds within oil,the ability of the catalyst(W-SiO2-20) under the same conditions to remove sulfur compounds decreased in the order:4,6-dimethyldibenzothiophene Dibenzothiophene Benzothiophene 1-dodecanethiol.Additionally,they did not require organic solvents as an extractant in the heterogeneous oxidative desulfurization process.After seven separate catalytic cycles,the desulfurization efficiency was still as high as 90.3%.From the gas chromatography-mass spectrometer analysis,DBT was entirely oxidized to its corresponding sulfone DBTO2 after reaction.A mechanism for the heterogeneous desulfurization reaction was proposed. 展开更多
关键词 Heterogeneous oxidative desulfurization Tungsten species mesoporous silica One-pot synthesis ORGANOSULFUR
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Facile H2O2 Hydrothermal Synthesis of Bimodal Mesoporous Silica MCM-48 Spheres 被引量:2
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作者 田冬 雍国平 +1 位作者 童红武 刘少民 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第4期479-483,I0002,共6页
The ordered bimodal mesoporous silica MCM-48 spheres were facile synthesized by mild- temperature post-synthesis H2O2 hydrothermal treatment of as-synthesized MCM-48. The results showed that H2O2 is indispensable for ... The ordered bimodal mesoporous silica MCM-48 spheres were facile synthesized by mild- temperature post-synthesis H2O2 hydrothermal treatment of as-synthesized MCM-48. The results showed that H2O2 is indispensable for simultaneously removing organic templates and forming ordered bimodal mesoporous silica MCM-48 spheres. The bimodal mesoporous MCM-48 was characterized by X-ray diffraction, transmission electron micrographs, FT-IR, and N2 adsorption-desorption, and a possible mechanism was proposed for the formation of bimodal mesoporous MCM-48. 展开更多
关键词 MCM-48 Bimodal mesoporous silica Hydrothermal method H2O2
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Gold nanoparticle stabilization within tailored cubic mesoporous silica:Optimizing alcohol oxidation activity 被引量:1
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作者 洪伟 闫晓庆 +1 位作者 李仁宏 范杰 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第3期545-553,共9页
Stabilizing gold nanoparticles(AuNPs) within a desired size range is critical to realize their promising catalytic performance in many important reactions.Herein,we investigate the anti-sintering properties of cubic... Stabilizing gold nanoparticles(AuNPs) within a desired size range is critical to realize their promising catalytic performance in many important reactions.Herein,we investigate the anti-sintering properties of cubic mesoporous silica(FDU-12) as a function of pore entrance size.Simple adjustments to the type of organic template and reaction temperature enable the successful synthesis of FDU-12 with controllable entrance sizes( 3,3-5 and 7 nm).Excellent anti-sintering properties are observed for FDU-12 with a sub-5-nm entrance size(3-5 nm) over a wide loading concentration(1.0-8.3 wt%) and the AuNPs can be stabilized within a 4.5-5.0-nm range after calcination at 550 ℃in air for 5 h.Smaller entrance size( 3 nm) prevents ingress of 3-nm AuNPs to the mesopores and results in low loading capacity and sintering.Conversely,FDU-12 possessing a larger entrance size(7 nm) shows promising anti-sintering properties at high loading concentrations,although catalytic performance is significantly lost at lower concentrations(e.g.2.1 wt%,14.2 ± 5.5 nm).Different anti-sintering mechanisms are proposed for each of the different FDU-12 entrance sizes.Additionally,catalytic data indicates that the obtained 4.5-nm AuNPs supported on FDU-12 with a sub-5-nm entrance size exhibit excellent mass-specific activity(1544 mmol g_(Au)^(-1) h^(-1)) and selectivity( 99%)at 230 ℃ for the gas-phase selective oxidation of cyclohexanol. 展开更多
关键词 Gold nanoparticle Cubic mesoporous silica Entrance size Anti-sintering property Alcohol oxidation
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Selective catalytic oxidation of NO over iron and manganese oxides supported on mesoporous silica 被引量:12
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作者 Junfeng Zhang Yan Huang Xia Chen 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第3期273-277,共5页
The selective catalytic oxidation (SCO) of NO was studied on a catalyst consisting of iron-manganese oxide supported on mesoporous silica (MPS) with different Mn/Fe ratios. Effects of the amount of manganese and i... The selective catalytic oxidation (SCO) of NO was studied on a catalyst consisting of iron-manganese oxide supported on mesoporous silica (MPS) with different Mn/Fe ratios. Effects of the amount of manganese and iron, oxygen, and calcination temperature on NO conversion were also investigated. It was found that the Mn-Fe/MPS catalyst with a Mn/Fe molar ratio of 1 showed the highest activity at the calcination temperature of 400 °C. The results showed that over this catalyst, NO conversion reached 70% under the condition of 280 °C and a space velocity of 5000 h-1. SO2 and H2O had no adverse impact on the reaction activity when the SCO reaction temperature was above 240 °C. In addition, the SCO activity was suppressed gradually in the presence of SO2 and H2O below 240 °C, and such an effect was reversible after heating treatment. 展开更多
关键词 selective catalytic oxidation of NO nitrogen monoxide mesoporous silica IRON MANGANESE
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Photocatalytic Oxidative Desulfurization of Dibenzothiophene on TiO2 Modified Bimodal Mesoporous Silica 被引量:7
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作者 Xu Meizhen Yang Lina Li Jian 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2017年第3期59-67,共9页
By using the bimodal mesoporous silica(BMMS) as the carrier and butyl titanate as the titanium source, the TiO_2/BMMS catalyst was prepared. The samples were characterized by XRD, XRF, N_2 adsorption and desorption, F... By using the bimodal mesoporous silica(BMMS) as the carrier and butyl titanate as the titanium source, the TiO_2/BMMS catalyst was prepared. The samples were characterized by XRD, XRF, N_2 adsorption and desorption, FTIR, UVvis,SEM, EDS, and TEM techniques. The test results showed that TiO_2 was amorphous, the TiO_2/BMMS catalyst had an ordered bimodal mesoporous structure, and the chemical interaction existed between BMMS and TiO_2. Since the TiO_2/BMMS had a lower band gap, its photocatalytic activity was better than TiO_2. Under UV irradiation a one-pot PODS system was set up, using TiO_2/BMMS as the catalyst, H_2O_2 as the oxidant, and methanol as the solvent. The TiO_2/BMMS catalyst showed better photocatalytic activity than the mono-modal mesoporous TiO_2/SBA-15 catalyst, and the desulfurization rate of dibenzothiophene(DBT) over TiO_2/BMMS catalyst could reach 99._2%. The TiO_2/BMMS catalyst also had so good stability that the desulfurization rate of DBT did not drop apparently after 8 cycles of reusing, and could still be close to 90%. 展开更多
关键词 BIMODAL mesoporous silica amorphous TIO2 PHOTOCATALYTIC activity UV irradiation DIBENZOTHIOPHENE
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In Situ Synthesis of Fluorescent Mesoporous Silica–Carbon Dot Nanohybrids Featuring Folate Receptor-Overexpressing Cancer Cell Targeting and Drug Delivery 被引量:5
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作者 Shuai Zhao Shan Sun +6 位作者 Kai Jiang Yuhui Wang Yu Liu Song Wu Zhongjun Li Qinghai Shu Hengwei Lin 《Nano-Micro Letters》 SCIE EI CAS CSCD 2019年第2期193-205,共13页
Multifunctional nanocarrier-based theranostics is supposed to overcome some key problems in cancer treatment.In this work,a novel method for the preparation of a fluorescent mesoporous silica–carbon dot nanohybrid wa... Multifunctional nanocarrier-based theranostics is supposed to overcome some key problems in cancer treatment.In this work,a novel method for the preparation of a fluorescent mesoporous silica–carbon dot nanohybrid was developed.Carbon dots(CDs),from folic acid as the raw material,were prepared in situ and anchored on the surface of amino-modified mesoporous silica nanoparticles(MSNs–NH2) via a microwave-assisted solvothermal reaction.The as-prepared nanohybrid(designated MSNs–CDs) not only exhibited strong and stable yellow emission but also preserved the unique features of MSNs(e.g.,mesoporous structure,large specific surface area,and good biocompatibility),demonstrating a potential capability for fluorescence imagingguided drug delivery.More interestingly,the MSNs–CDs nanohybrid was able to selectively target folate receptor-overexpressing cancer cells(e.g.,HeLa),indicating that folic acid still retained its function even after undergoing the solvothermal reaction.Benefited by these excellent properties,the fluorescent MSNs–CDs nanohybrid can be employed as a fluorescence-guided nanocarrier for the targeted deliveryof anticancer drugs(e.g.,doxorubicin),thereby enhancing chemotherapeutic efficacy and reducing side effects.Our studies may provide a facile strategy for the fabrication of multifunctional MSN-based theranostic platforms,which is beneficial in the diagnosis and therapy of cancers in future. 展开更多
关键词 mesoporous silica nanoparticles CARBON DOTS Fluorescence imaging Targeted drug delivery Chemotherapy
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SYNTHESIS OF MESOPOROUS POLY(STYRENE-co-MALEIC ANHYDRIDE)/SILICA HYBRID MATERIALS VIA A NONSURFACTANT-TEMPLATED SOL-GEL PROCESS 被引量:6
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作者 Jie-bin Pang Kun-yuan Qiu Yen Wei Department of Polymer Science and Engineering, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China. Department of Chemistry, Drexel University, Philadelphia, Pennsylvania 19104, USA. 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2000年第5期469-472,共4页
Mesoporous poly(styrene-co-maleic anhydride)/silica hybrid materials have been prepared. The synthesis was achieved by the HCl-catalyzed sol-gel reactions of tetraethyl orthosilicate (TEOS) and styrene-maleic anhydrid... Mesoporous poly(styrene-co-maleic anhydride)/silica hybrid materials have been prepared. The synthesis was achieved by the HCl-catalyzed sol-gel reactions of tetraethyl orthosilicate (TEOS) and styrene-maleic anhydride copolymer in the presence of 3-aminopropyl triethoxysilane (APTES) as a coupling agent and citric acid as a nonsurfactant template or pore-forming agent, followed by ethanol extraction. Characterization results from nitrogen sorption isotherms and powder X-ray diffraction indicate that polymer-modified mesoporous materials with large specific surface areas (e.g. 900 m(2)/g) and pore volumes (e.g. 0.6 cm(3)/g) could be prepared. As the citric acid concentration is increased, the specific surface areas, pore volumes and pore diameters of the hybrid materials increase. 展开更多
关键词 mesoporous hybrid material poly(styrene-co-maleic anhydride)/silica citric acid nonsurfactant template sol-gel process
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Oxidation of NO over cobalt oxide supported on mesoporous silica 被引量:5
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作者 Yan Huang Dongmei Gao Zhiquan Tong Junfeng Zhang He Luo 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2009年第4期421-428,共8页
Cobalt oxide catalysts supported on mesoporous silica (Co3O4/MPS) were prepared, characterized and applied for catalytic oxidation of NO. Effects of catalyst supports, calcination temperatures, H2O and SO2 on NO con... Cobalt oxide catalysts supported on mesoporous silica (Co3O4/MPS) were prepared, characterized and applied for catalytic oxidation of NO. Effects of catalyst supports, calcination temperatures, H2O and SO2 on NO conversion were investigated. The samples were also characterized by BET, XRD, FTIR and TG/DTG. The results suggested that Co3O4/MPS catalyst calcined at 573 K had the smallest crystal particles and the best surface dispersion. This catalyst had the highest activity and yielded 82% NO conversion at 573 K, at a space velocity of 12000 h^-1. Although the conversion of NO decreased with the introduction of H2O, it could be restored completely after removing residual H2O from Co3O4/MPS catalyst by heating at 573 K. In the presence of SO2, the oxidation activity decreased and COSO4 was detected on the catalyst. The NO conversion decreased to 30.2% in the presence of SO2 and H2O. It could not be restored completely after cutting off H2O and SO2. The deactivation of the catalyst in the presence of SO2 and H2O was attributed to the formation of cobalt sulfate species. 展开更多
关键词 catalytic oxidation NO Co3O4/mesoporous silica H2O SO2
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Synthesis and Characterization of Carboxyl-terminated Polyethylene Glycol Functionalized Mesoporous Silica Nanoparticles 被引量:3
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作者 WANG Yu LIU Mingxing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第6期1540-1545,共6页
Colloidal mesoporous silica nanoparticles functionalized with carboxy-terminated polyethylene glycol(CMS-PEG-COOH) were successfully synthesized by covalently grafting dicarboxy-terminated polyethylene glycol(HOOC-PEG... Colloidal mesoporous silica nanoparticles functionalized with carboxy-terminated polyethylene glycol(CMS-PEG-COOH) were successfully synthesized by covalently grafting dicarboxy-terminated polyethylene glycol(HOOC-PEG-COOH) on the surface of the amino functionalized CMS nanoparticles with amide bond as a cross linker. Moreover, the structural and particle properties of CMS-PEG-COOH were characterized by nuclear magnetic resonance spectroscopy(1 H-NMR), transmission electron microscopy(TEM), dynamic light scattering(DLS), nitrogen adsorption-desorption measurements, X-ray diffraction(XRD), and Fourier transform infrared spectroscopy(FT-IR). The nanomaterials presented a relatively uniform spherical shape morphology with diameters of about 120 nm,and favorable dispersibility in weak acid solution. The CMSPEG-COOH exhibited no changes in the state of amorphous, while the mesopores sizes of 5.25 nm might provide the nanomaterials with large capacity for the loading and releasing of drugs. So the results indicated that CMSPEG-COOH might be a critical nanomaterial for drug delivery system in the future. 展开更多
关键词 mesoporous silica nanoparticles polyethylene glycol FUNCTIONALIZATION carboxy-terminated synthesis
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Low-cost preparation of mesoporous silica with high pore volume 被引量:4
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作者 Shuling Shen Wei Wu +1 位作者 Kai Guo Jianfeng Chen 《Journal of University of Science and Technology Beijing》 CSCD 2007年第4期369-372,共4页
Mesoporous silica materials with high pore volume were successfully prepared by the chemical precipitation method, with water glass and a biodegradable nonionic surfactant polyethylene glycol (PEG). The obtained mat... Mesoporous silica materials with high pore volume were successfully prepared by the chemical precipitation method, with water glass and a biodegradable nonionic surfactant polyethylene glycol (PEG). The obtained materials were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), thermo gravimetric analyzer and differential scanning calorimetry (TG-DSC), nitrogen adsorption-desorption measurements, and X-ray diffraction (XRD). The results showed that the changes of the pore parameters depended on both the surfactant content and heat treatment temperature. When the content of PEG was 10wt% and the obtained PEG/SiO2 composite was heated at 600℃, the mesoporous silica with a pore volume of 2.2 cma/g, a BET specific surface area of 361.55 m^2/g, and a diameter of 2-4 μm could be obtained. The obtained mesoporous silica materials have potential applications in the fields of paint and plastic, as thickening, reinforcing, and flatting agents. 展开更多
关键词 mesoporous silica chemical precipitation high pore volume water glass nonionic surfactant
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An Oxidative Desulfurization Catalyst Based on Bimodal Mesoporous Silica Containing Quaternary Ammonium Heteropolyphosphamolybdenum 被引量:4
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作者 Li Jian Wu Haishun +1 位作者 Yang Lina Ma Bo 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2016年第2期33-42,共10页
A bimodal mesoporous silica(BMMS) modified with amphiphilic compound(C_(19)H_(42)N)_3(PMo_(12)O_(40))(CTA-PMO) was prepared by the two-step impregnation method. Firstly, H3PMo12O40 was introduced into the bimodal meso... A bimodal mesoporous silica(BMMS) modified with amphiphilic compound(C_(19)H_(42)N)_3(PMo_(12)O_(40))(CTA-PMO) was prepared by the two-step impregnation method. Firstly, H3PMo12O40 was introduced into the bimodal mesoporous silica via impregnation, then C_(19)H_(42)NBr(CTAB) was grafted on the surface of BMMS containing H3PMo12O40 based on the chemical reaction between quaternary ammonium compound and the phosphomolybdic acid, and then the catalyst CTAPMO/BMMS was obtained. The samples were characterized by XRD, N_2 adsorption and desorption, FTIR, 31P-NMR, 29Si-NMR and TEM analyses. It is shown that the catalyst has a typical bimodal mesoporous structure, in which the small mesopore diameter is about 3.0 nm and the large mesopore diameter is about 5.0 nm. The chemical interaction happens between the Keggin structure and silica group of BMMS. Compared with the mono-modal porous Hβ and SBA-15 zeolites modified with CTA-PMO, CTA-PMO/BMMS showed better catalytic activity in the oxidative conversion of dibenzothiophene(DBT), and the desulfurization rate can reach about 94% with the help of extraction, and the catalyst can be separated by filtration and reused directly. The catalytic oxidative desulfurization mechanism on CTA-PMO/BMMS was proposed and verified. 展开更多
关键词 (C19H42N)3(PMo12O40) AMPHIPHILIC BIMODAL mesoporous silica oxidation DIBENZOTHIOPHENE
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pH-responsive mesoporous silica nanoparticles employed in controlled drug delivery systems for cancer treatment 被引量:8
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作者 Ke-Ni Yang Chun-Qiu Zhang +3 位作者 Wei Wang Paul C.Wang Jian-Ping Zhou Xing-Jie Liang 《Cancer Biology & Medicine》 SCIE CAS CSCD 2014年第1期34-43,共10页
In the fight against cancer, controlled drug delivery systems have emerged to enhance the therapeutic efficacy and safety of anti-cancer drugs. Among these systems, mesoporous silica nanoparticles (MSNs) with a func... In the fight against cancer, controlled drug delivery systems have emerged to enhance the therapeutic efficacy and safety of anti-cancer drugs. Among these systems, mesoporous silica nanoparticles (MSNs) with a functional surface possess obvious advantages and were thus rapidly developed for cancer treatment. Many stimuli-responsive materials, such as nanopartides, polymers, and inorganic materials, have been applied as caps and gatekeepers to control drug release from MSNs. This review presents an overview of the recent progress in the production of pH-responsive MSNs based on the pH gradient between normal tissues and the tumor microenvironment. Four main categories of gatekeepers can respond to acidic conditions. These categories will be described in detail. 展开更多
关键词 mesoporous silica nanoparticles PH-RESPONSIVE controlled drug release drug delivery systems antineoplastic protocols
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Synthesis of mesoporous high‐silica zeolite Y and their catalytic cracking performance 被引量:4
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作者 Wenhao Cui Dali Zhu +7 位作者 Juan Tan Nan Chen Dong Fan Juan Wang Jingfeng Han Linying Wang Peng Tian Zhongmin Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第7期1945-1954,共10页
Mesoporous high‐silica zeolite Y with advantages of improved accessibility of acid sites and mass transport properties is highly desired catalytic materials for oil refinery,fine chemistry and emerg‐ing biorefinery.... Mesoporous high‐silica zeolite Y with advantages of improved accessibility of acid sites and mass transport properties is highly desired catalytic materials for oil refinery,fine chemistry and emerg‐ing biorefinery.Here,we report the direct synthesis of mesoporous high‐silica zeolite Y(named MSY,SiO_(2)/Al2O_(3)≥9.8)and their excellent catalytic cracking performance.The obtained MSY mate‐rials are mesoporous single crystals with octahedral morphology,abundant mesoporosity and ex‐cellent(hydro)thermal stability.Both the acid concentration and acid strength of H‐form MSY are obviously higher than those of commercial ultra‐stable Y(USY),which should be attributed to the uniform Al distribution of MSY zeolite.The H‐MSY displays an obviously reduced deactivation rate and improved catalytic activity in the cracking reaction of bulky 1,3,5‐triisopropylbenzene(TIPB),as compared with its mesoporogen‐free counterpart and USY.In addition,H‐MSY was investigated as catalyst for the cracking of industrial heavy oil.The MSY‐based catalyst(after aging at 800 oC in 100%steam for 17 h)exhibits superior conversion(7.64%increase)and gasoline yield(16.37%increase)than industrial fluid catalytic cracking(FCC)catalyst under the investigated conditions. 展开更多
关键词 mesoporous zeolite FAU SYNTHESIS High‐silica zeolite Y Fluid catalytic cracking
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Dual-functional pyrene implemented mesoporous silicon material used for the detection and adsorption of metal ions
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作者 Jing Huang Honghui Cai +3 位作者 Qian Zhao Yunpeng Zhou Haibo Liu Jing Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第8期108-117,共10页
A fluorescent active organic–inorganic hybrid material Py N-SBA-15 was synthesized by implementing pyrene derivatives into mesoporous SBA-15 silica.Py N-SBA-15 had detection and removal functionalities toward Al^(3+)... A fluorescent active organic–inorganic hybrid material Py N-SBA-15 was synthesized by implementing pyrene derivatives into mesoporous SBA-15 silica.Py N-SBA-15 had detection and removal functionalities toward Al^(3+),Cu^(2+),and Hg^(2+).On the one hand,Py N-SBA-15 was used as a fluorescence sensor and displayed high sensitivity toward Al^(3+),Cu^(2+),and Hg^(2+)cations (limit of detection:8.0×10^(-7),1.1×10^(-7),and 2.9×10^(-6)mol·L^(–1),respectively) among various analytes with“turn-off”response.On the other hand,the adsorption studies for these toxic analytes (Cu^(2+),Hg^(2+),and Al^(3+)) showed that the ion removal capacity could reach up to 45,581,and 85 mg·g^(-1),respectively.Moreover,the Langmuir isotherm models were better fitted with the adsorption data,indicating that the adsorption was mono-layer adsorption.Kinetic analysis revealed that the adsorption process was well described by the pseudo-second-order kinetic model for Cu^(2+)and Hg^(2+)and pseudo-first-order kinetic model for Al^(3+).The prepared silica material could be reused in four recycles without significantly decreasing its adsorption capacity.Therefore,the Py N-SBA-15 material can serve as a promising candidate for the simultaneous rapid detection and efficient adsorption of metal ions. 展开更多
关键词 Dual function Nanomaterials mesoporous silica Metal ions Detection and adsorption
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