目的:制备负电荷的姜黄素炎症靶向自微乳给药系统(NC-CUR-SMEDDS),并对其进行质量评价。方法:在前期姜黄素自微乳(CUR-SMEDDS)的研究基础上,以乳剂的粒径、Zeta电位、包封率和载药量为评价指标,通过单因素试验筛选电荷调节剂的最佳用量...目的:制备负电荷的姜黄素炎症靶向自微乳给药系统(NC-CUR-SMEDDS),并对其进行质量评价。方法:在前期姜黄素自微乳(CUR-SMEDDS)的研究基础上,以乳剂的粒径、Zeta电位、包封率和载药量为评价指标,通过单因素试验筛选电荷调节剂的最佳用量,制备NC-CUR-SMEDDS。通过观察微乳外观和微观形态并测定其粒径、Zeta电位、包封率及载药量对其进行质量评价。结果:当加入处方量4%的丁二酸二辛酯磺酸钠时,所形成的微乳Zeta电位可以达到-43.43±0.29 m V,外观澄清、透明,粒径分布均匀,平均粒径为14.08±0.082 nm,姜黄素载药量为26.48 mg·g^(-1),包封率为94.12%。结论:NC-CUR-SMEDDS包封率高,带负电,粒径分布均匀,符合结肠炎症靶向要求。展开更多
Na-rich birnessite(NRB) was synthesized by a simple synthesis method and used as a high-efficiency adsorbent for the removal of ammonium ion(NH+4) from aqueous solution.In order to demonstrate the adsorption perf...Na-rich birnessite(NRB) was synthesized by a simple synthesis method and used as a high-efficiency adsorbent for the removal of ammonium ion(NH+4) from aqueous solution.In order to demonstrate the adsorption performance of the synthesized material,the effects of contact time,pH,initial ammonium ion concentration,and temperature were investigated.Adsorption kinetics showed that the adsorption behavior followed the pseudo second-order kinetic model.The equilibrium adsorption data were fitted to Langmuir and Freundlich adsorption models and the model parameters were evaluated.The monolayer adsorption capacity of the adsorbent,as obtained from the Langmuir isotherm,was 22.61 mg NH+4-N/g at283 K.Thermodynamic analyses showed that the adsorption was spontaneous and that it was also a physisorption process.Our data revealed that the higher NH+4adsorption capacity could be primarily attributed to the water absorption process and electrostatic interaction.Particularly,the high surface hydroxyl-content of NRB enables strong interactions with ammonium ion.The results obtained in this study illustrate that the NRB is expected to be an effective and economically viable adsorbent for ammonium ion removal from aqueous system.展开更多
Objective The changes in serum adipokines and cytokines related to oxidative stress were examined during 3 months ‘Off to On’ and ‘On to Off’ periods using negatively charged particle-dominant indoor air condition...Objective The changes in serum adipokines and cytokines related to oxidative stress were examined during 3 months ‘Off to On’ and ‘On to Off’ periods using negatively charged particle-dominant indoor air conditions(NCPDIAC).Methods Seven volunteers participated in the study,which included ‘OFF to 3 months ON’ periods(ON trials) for a total of 16 times,and ‘ON to 3 months OFF’(OFF trials) periods for a total of 13 times.Results With the exception of one case,serum amyloid A(SAA) levels decreased significantly during the ON trials.Conclusion Considering that SAA is an acute phase reactive protein such as C reactive protein(CRP),this observed decrease might indicate the prevention of cardiovascular and atherosclerotic changes,since an increase in high-sensitive CRP is associated with the subsequent detection of these events.展开更多
通过特定的化学反应对截留分子量为30 k D的再生纤维素(RC)超滤膜进行改性,得到荷负电超滤膜,并研究了其表面荷电性能。选用腐殖酸作为天然有机物的代表物质,研究荷负电改性膜同时去除溶液中腐殖酸和铅离子,主要考察了p H值和腐殖酸铅...通过特定的化学反应对截留分子量为30 k D的再生纤维素(RC)超滤膜进行改性,得到荷负电超滤膜,并研究了其表面荷电性能。选用腐殖酸作为天然有机物的代表物质,研究荷负电改性膜同时去除溶液中腐殖酸和铅离子,主要考察了p H值和腐殖酸铅离子络合作用对两者截留率的影响,并对比了荷负电膜和未改性膜去除天然有机物和铅离子的研究结果。得到如下结论:(1)在酸性及中性溶液环境下,随着p H值的升高,荷负电超滤膜对腐殖酸和铅离子的截留率都提高。(2)铅离子与腐殖酸共存时,腐殖酸铅离子络合体的荷负电性相比于原腐殖酸分子降低,荷负电超滤膜对混合溶液中腐殖酸的截留率有一定程度降低,络合在腐殖酸表面的铅离子随着腐殖酸的截留而被截留,铅离子截留率得到一定程度提升。(3)由于腐殖酸与铅离子络合体带负电,其与荷负电膜之间存在静电作用,所以荷负电改性膜对腐殖酸和铅离子的截留率比未改性中性膜高。展开更多
A series of amphiphilic copolymers containing poly(vinyl chloride-r-acrylic acid) (P(VC-r-AA)) was synthesized and used to prepare membranes via a non-solvent induced phase separation method. The prepared membra...A series of amphiphilic copolymers containing poly(vinyl chloride-r-acrylic acid) (P(VC-r-AA)) was synthesized and used to prepare membranes via a non-solvent induced phase separation method. The prepared membranes were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, and water contact angle and zeta potential measurements. The copolymer P(VC-r-AA) chains did not dissolved in a coagulation bath, indicating that the AA segments were completely retained within the membrane. Enriching degree of AA segments in surface layer was 2 for copolymer membrane. In addition, the introduction of AA segments made the membrane electronegative and hydrophilic so that the membrane was sensitive to the solution pH. The fouling resistance, adsorption of Cu(II), Cr(III) and Ce(IV) ions and the desorption properties of the membranes were also determined. The copolymer membranes exhibited good antifouling performance with a fouling reversibility of 92%. The membranes also had good adsorption capacities for Cu(II), Cr(III) and Ce(IV) ions. The optimal pH for Cu(II) adsorption was 6 and the copolymer membrane has potential applications for low concentration Cu(II) removal.展开更多
Diamond negatively charged nitrogen-vacancy(NV-) centers provide an opportunity for the measurement of the Meissner effect on extremely small samples in a diamond anvil cell(DAC) due to their high sensitivity in detec...Diamond negatively charged nitrogen-vacancy(NV-) centers provide an opportunity for the measurement of the Meissner effect on extremely small samples in a diamond anvil cell(DAC) due to their high sensitivity in detecting the tiny change of magnetic field. We report on the variation of magnetic field distribution in a DAC as a sample transforms from normal to superconducting state by using finite element analysis. The results show that the magnetic flux density has the largest change on the sidewall of the sample, where NV-centers can detect the strongest signal variation of the magnetic field. In addition, we study the effect of magnetic coil placement on the magnetic field variation. It is found that the optimal position for the coil to generate the greatest change in magnetic field strength is at the place as close to the sample as possible.展开更多
文摘目的:制备负电荷的姜黄素炎症靶向自微乳给药系统(NC-CUR-SMEDDS),并对其进行质量评价。方法:在前期姜黄素自微乳(CUR-SMEDDS)的研究基础上,以乳剂的粒径、Zeta电位、包封率和载药量为评价指标,通过单因素试验筛选电荷调节剂的最佳用量,制备NC-CUR-SMEDDS。通过观察微乳外观和微观形态并测定其粒径、Zeta电位、包封率及载药量对其进行质量评价。结果:当加入处方量4%的丁二酸二辛酯磺酸钠时,所形成的微乳Zeta电位可以达到-43.43±0.29 m V,外观澄清、透明,粒径分布均匀,平均粒径为14.08±0.082 nm,姜黄素载药量为26.48 mg·g^(-1),包封率为94.12%。结论:NC-CUR-SMEDDS包封率高,带负电,粒径分布均匀,符合结肠炎症靶向要求。
基金supported by the National Natural Science Foundation of China(No.51278409)the Education Department of Shaanxi Province(No.15JS046)
文摘Na-rich birnessite(NRB) was synthesized by a simple synthesis method and used as a high-efficiency adsorbent for the removal of ammonium ion(NH+4) from aqueous solution.In order to demonstrate the adsorption performance of the synthesized material,the effects of contact time,pH,initial ammonium ion concentration,and temperature were investigated.Adsorption kinetics showed that the adsorption behavior followed the pseudo second-order kinetic model.The equilibrium adsorption data were fitted to Langmuir and Freundlich adsorption models and the model parameters were evaluated.The monolayer adsorption capacity of the adsorbent,as obtained from the Langmuir isotherm,was 22.61 mg NH+4-N/g at283 K.Thermodynamic analyses showed that the adsorption was spontaneous and that it was also a physisorption process.Our data revealed that the higher NH+4adsorption capacity could be primarily attributed to the water absorption process and electrostatic interaction.Particularly,the high surface hydroxyl-content of NRB enables strong interactions with ammonium ion.The results obtained in this study illustrate that the NRB is expected to be an effective and economically viable adsorbent for ammonium ion removal from aqueous system.
基金supported by a Kawasaki Medical School Research Grant(28B051)
文摘Objective The changes in serum adipokines and cytokines related to oxidative stress were examined during 3 months ‘Off to On’ and ‘On to Off’ periods using negatively charged particle-dominant indoor air conditions(NCPDIAC).Methods Seven volunteers participated in the study,which included ‘OFF to 3 months ON’ periods(ON trials) for a total of 16 times,and ‘ON to 3 months OFF’(OFF trials) periods for a total of 13 times.Results With the exception of one case,serum amyloid A(SAA) levels decreased significantly during the ON trials.Conclusion Considering that SAA is an acute phase reactive protein such as C reactive protein(CRP),this observed decrease might indicate the prevention of cardiovascular and atherosclerotic changes,since an increase in high-sensitive CRP is associated with the subsequent detection of these events.
文摘通过特定的化学反应对截留分子量为30 k D的再生纤维素(RC)超滤膜进行改性,得到荷负电超滤膜,并研究了其表面荷电性能。选用腐殖酸作为天然有机物的代表物质,研究荷负电改性膜同时去除溶液中腐殖酸和铅离子,主要考察了p H值和腐殖酸铅离子络合作用对两者截留率的影响,并对比了荷负电膜和未改性膜去除天然有机物和铅离子的研究结果。得到如下结论:(1)在酸性及中性溶液环境下,随着p H值的升高,荷负电超滤膜对腐殖酸和铅离子的截留率都提高。(2)铅离子与腐殖酸共存时,腐殖酸铅离子络合体的荷负电性相比于原腐殖酸分子降低,荷负电超滤膜对混合溶液中腐殖酸的截留率有一定程度降低,络合在腐殖酸表面的铅离子随着腐殖酸的截留而被截留,铅离子截留率得到一定程度提升。(3)由于腐殖酸与铅离子络合体带负电,其与荷负电膜之间存在静电作用,所以荷负电改性膜对腐殖酸和铅离子的截留率比未改性中性膜高。
基金This research was supported by the National High Technology Research and Development Program of China (Granted No. 2012AA03A602 ) , the National Basic Research Program of China (Granted No. 2009CB623402) and the National Natural Science Foundation of China (Grant No. 20974094).
文摘A series of amphiphilic copolymers containing poly(vinyl chloride-r-acrylic acid) (P(VC-r-AA)) was synthesized and used to prepare membranes via a non-solvent induced phase separation method. The prepared membranes were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, and water contact angle and zeta potential measurements. The copolymer P(VC-r-AA) chains did not dissolved in a coagulation bath, indicating that the AA segments were completely retained within the membrane. Enriching degree of AA segments in surface layer was 2 for copolymer membrane. In addition, the introduction of AA segments made the membrane electronegative and hydrophilic so that the membrane was sensitive to the solution pH. The fouling resistance, adsorption of Cu(II), Cr(III) and Ce(IV) ions and the desorption properties of the membranes were also determined. The copolymer membranes exhibited good antifouling performance with a fouling reversibility of 92%. The membranes also had good adsorption capacities for Cu(II), Cr(III) and Ce(IV) ions. The optimal pH for Cu(II) adsorption was 6 and the copolymer membrane has potential applications for low concentration Cu(II) removal.
基金supported by the National Key R&D Program of China(Grant No.2018YFA0305900)the National Natural Science Foundation of China(Grant Nos.11774126,11674404,and 51772125)
文摘Diamond negatively charged nitrogen-vacancy(NV-) centers provide an opportunity for the measurement of the Meissner effect on extremely small samples in a diamond anvil cell(DAC) due to their high sensitivity in detecting the tiny change of magnetic field. We report on the variation of magnetic field distribution in a DAC as a sample transforms from normal to superconducting state by using finite element analysis. The results show that the magnetic flux density has the largest change on the sidewall of the sample, where NV-centers can detect the strongest signal variation of the magnetic field. In addition, we study the effect of magnetic coil placement on the magnetic field variation. It is found that the optimal position for the coil to generate the greatest change in magnetic field strength is at the place as close to the sample as possible.