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Reaction intermediates and products characterisation of NH_(3) in desulphurisation with activated coke

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Journal of Iron and Steel Research International 2024年第11期31卷 2664-2674页

作者： Wei-li Zhang Meng Wang Wen-zhe Si jun-hua li School of Environment Tsinghua UniversityBeijing100084China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China

The sulphate is an important factor restricting the efficient and stable operation of the activated coke (AC) flue gas purification system. The simulation experiments and in situ infrared tests of AC taken from desorption tower of the AC flue gas purification system were carried out to first calibrate the thermal desorption characteristics of adsorbed NH_(3) and sulphate and explore the reaction behaviour of NH_(3) with SO_(2) and H_(2)SO_(4). On this basis, some advice for optimising the sulphate generation was put forward to improve the purification efficiency of the AC system. The results show that the temperatures of the desorption of adsorbed NH_(3), the decomposition of (NH_(4))_(2)SO_(4) and NH_(4)HSO_(4) are 224, 276 and 319 ℃, respectively, which lays the foundation for the quantitative analysis of sulphate on AC. Regardless of the NH_(3) amount, only a small portion of H_(2)SO_(4) is converted to sulphate, as the H_(2)SO_(4) deposited in AC pores or agglomerated together could not come into contact with NH_(3). The final reaction product of NH_(3) and SO_(2) is mainly (NH_(4))_(2)SO_(4) which is continuously generated because the newly generated H_(2)SO_(4) is continually exposed to NH_(3), if NH_(3) is enough. The reaction of NH_(3) with H_(2)SO_(4) takes precedence over with NH_(4)HSO_(4). In the initial stages in which H_(2)SO_(4) is exposed to NH_(3), the product is essentially all NH_(4)HSO_(4) as intermediate. Then, it is further converted to (NH_(4))_(2)SO_(4) whose amount reaches equilibrium when the accessible H_(2)SO_(4) is exhausted. All the NH_(3) adsorbed on AC entering the desulphurisation tower generates NH_(4)HSO_(4), but the amount is limited. The remaining SO_(2) entering the denitrification tower mainly generates (NH_(4))_(2)SO_(4);thus, limiting the remaining SO_(2) amount is necessary to guarantee denitrification efficiency. When the NH_(3) injection is changed to the desulphurisation tower, the initial NH_(3) injection rate can be inc

关键词： Sulphate generation Activated coke Sintering flue gas treatment NH4HSO4 (NH4)2SO4

Action of Schwann Cells Implanted in Cerebral Hemorrhage Lesion

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Biomedical and Environmental Sciences 2007年第1期20卷 47-51页

作者： HONG WAN SHAO-DONG ZHANG jun-hua li Beijing Neurosurgical Institute Capital Medical University Beijing 100050 China

Objective To investigate whether there is neogenesis of myelin sheath and neuron after transplantation of Schwann cells into cerebral hemorrhage lesion. Methods Schwann cells were expanded, labeled with BrdU in vitro and transplanted into rat cerebral hemorrhage with blood extracted from femoral artery and then injected into the basal nuclei. Double immunohistochemistry staining and electron microscopy were used to detect the expression of BrdU/MBP and BrdU/GAP-43 and remyelination. Results BrdU/MBP double positive cells could be seen at 1 week up to 16 weeks after transplantation of Schwann cells. Thin remyelination was observed under electron microscope. GAP-43 positive cells appeared after 12 weeks and were found more in Hippocamp. Conclusions Grafted Schwann cells participate in remyelination and promoter nerve restore in rat cerebral hemorrhage.

关键词： Schwann cell MBP GAP-43

Fe Promotion Effect in Mn/USY for Low-temperature Selective Catalytic Reduction of NO with NH_(3)

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Chinese Chemical Letters 2006年第7期17卷 991-994页

作者： Qi Chun liN Ji Ming HAO jun hua li Department of Environmental Science and Engineering Tsinghua University Beijing 100084

A series of catalysts of Mn/USY and Mn-Fe/USY prepared by impregnation were studied for low-temperature selective catalytic reduction （SCR） of NO with NH3 in the presence of excess of oxygen. It was found that the addition of Fe enhanced the catalytic performance at low-temperature. Mn-Fe/USY catalyst yielded nearly 100% NO conversion in a range of temperature from 423 to 573 K at a space velocity of 36 000 cm3g^-1·h^-1. Coexistence of manganese and iron oxides enhanced the dispersion of the supported oxides, no visible phase of the oxides can be observed on catalyst. The addition of Fe enhanced the number and strength of the Bronsted and Lewis acid sites on the surface of the catalyst, which might promote the absorption of NH3 to form active intermediate and enhance the catalytic performance at low-temperature.

关键词： Low-temperature SCR Mn/USY Mn-Fe/USY SCR of NO with NH3.

Induction of Functional Recovery by Co-transplantation of Neural Stem Cells and Schwann Cells in a Rat Spinal Cord Contusion Injury Model

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Biomedical and Environmental Sciences 2007年第3期20卷 242-249页

作者： JIN li CHONG-RAN SUNN HAN ZHANG KAM-SZE TSANG jun-hua li SHAO-DONG ZHANG YI-hua AN Beijing Neurosurgical Institute Capital University of Medical Science Beijing 100050 China Blood and Marrow Transplantation Department of Anatomical and Cellular Pathology the Chinese University of Hong Kong Prince of Wales Hospital Hong Kong China

Objective To study the transplantation efficacy of neural stem cells （NSCs） and Schwann cells （SC） in a rat model of spinal cord contusion injury. Methods Multipotent neural stem cells （NSCs） and Schwann cells were harvested from the spinal cords of embryonic rats at 16 days post coitus and sciatic nerves of newborn rats, respectively. The differential characteristics of NSCs in vitro induced by either serum-based culture or co-culture with SC were analyzed by immunofluorescence. NSCs and SCs were co-transplanted into adult rats having undergone spinal cord contusion at T9 level. The animals were weekly monitored using the Basso-Beattie-Bresnahan locomotor rating system to evaluate functional recovery from contusion-induced spinal cord injury. Migration and differentiation of transplanted NSCs were studied in tissue sections using immunohistochemical staining. Results Embryonic spinal cord-derived NSCs differentiated into a large number of oligodendrocytes in serum-based culture upon the withdrawal of mitogens. In cocultures with SCs, NSCs differentiated into neuron more readily. Rats with spinal cord contusion injury which had undergone transplantation of NSCs and SCs into the intraspinal cavity demonstrated a moderate improvement in motor functions. Conclusions SC may contribute to neuronal differentiation of NSCs in vitro and in vivo. Transplantation of NSCs and SCs into the affected area may be a feasible approach to promoting motor recovery in patients after spinal cord injury.

关键词： Spinal cord injury Transplantation Neural stem cells Schwann cells Cell differentiation

Enhancement of Activity of SnO_(2)-doped In_(2)O_(3)/Al_(2)O_(3) Catalyst for NO Reduction with Propene in the Presence of H_(2)O and SO_(2)

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Chinese Chemical Letters 2005年第11期16卷 1535-1538页

作者： Xiang Yu CUI jun hua li Ji Ming HAO li Xin FU Department of Environmental Science and Engineering Tsinghua University Beijing 100084

The novel bimetallic Sn-Im/Al2O3 catalysts prepared by three methods for NO reduction by propene were investigated. The results showed that the catalytic activity was enhanced significantly in the presence of H2O on sol-gel catalyst, and the maximum NO conversion increased from 46% to 92%, even in the presence of 100 ppm SO2, NO conversion was still 80%.

关键词： Selective catalytic reduction De-NOx lean burn In2O3/Al2O3 Sn-Ir/A12O3.

Synthesis and Crystal Structure of a Novel 1D Magnesium(II) Coordination Polymer Constructed by L-Cysteic Acid

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Chinese Journal of Structural Chemistry 2007年第8期26卷 907-910页

作者： li Hai-Ye liAO Bei-ling JIANG Yi-Min ZHANG Shu-hua li jun-Xia College of Chemistry and Chemical Engineering Guangxi Normal University Guilin 541004 China

A novel coordination polymer [Mg（L）（H2O）2]·H2O] （LH2=L-cysteic acid） has been synthesized and characterized by elemental analysis, IR and single-crystal X-ray *** crystal crystallizes in orthorhombic system, space group P212121, with a=5.962（3）, b=11.224（6）, c=13.664（7）A, V=914.3（8）A^3, Z=4, Mr=245.50, Dc=1.783 g/cm^3,μ=0.445 mm-1,flack parameter=0.32（16）, F（000）=512, the final R=0.0458 and wR=0.1172 for 1578 observed reflections with I 〉 2σ（Ⅰ）. The Mg（Ⅱ） atom shows an octahedral geometry defined by two carboxyl O atoms from two different L-cysteic acid ligands, one carboxyl O atom and one amino N atom from the adjacent ligand, and two aqua ligands. The Mg（Ⅱ） atoms are bridged by L-cysteic acid ligands, leading to a 1D infinite zigzag chain. In the structure there are extensive hydrogen bonds,through which the complex completes its 3D framework structure.

关键词： magnesium(Ⅱ) complex L-cysteic acid synthesis crystal structure

In vitro protective effect of recombinant prominin-1 combined with microRNA-29b on N-methyl-D-aspartateinduced excitotoxicity in retinal ganglion cells

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International Journal of Ophthalmology(English edition) 2023年第11期16卷 1746-1755页

作者： jun-hua li Guan-Shun Yu Yu-Da Wang Tian-Kun li Eye Hospital and School of Ophthalmology and Optometry Wenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina Eye Hospital of Wenzhou Medical University Hangzhou Branch Hangzhou 310020Zhejiang ProvinceChina Tianjin Eye Hospital Tianjin 300020China

AIM:To determine the in vitro protective effect of recombinant prominin-1(Prominin-1)+microRNA-29b(P1M29)on N-methyl-D-aspartate(NMDA)-induced excitotoxicity in retinal ganglion cells(RGCs).METHODS:RGC-5 cells were cultured,and NMDAinduced excitotoxicity at the range of 100–800μmol/L was assessed using the MTT ***(800μmol/L)was selected as the appropriate concentration for preparing the cell *** evaluate the protective effect of P1M29 on the cell model,Prominin-1 was added at the concentration of 1–6 ng/mL for 48h,and the cell survival was investigated with/without *** obtaining the appropriate concentration and time of P1M29 at 48h,real-time polymerase chain reaction(PCR)was utilized to detect the relative mRNA expression of vascular endothelial growth factor(VEGF)and transforming growth factor(TGF)-β*** blot detection was applied to measure the phosphorylation levels of protein kinase B(AKT)and extracellular regulated protein kinases(ERK)in RGC-5 cells after treatment with *** study of the cell model was conducted by flow cytometry for estimating the anti-apoptotic effect of *** analysis was used to analyze the expression levels of VEGF and TGF-β***:MTT cytotoxicity assays demonstrated that P1M29 group had significantly higher cell survival rate than Prominin-1 group(P<0.05).Real-time PCR data indicated that the expression levels of VEGF were significantly increased in both Prominin-1 and P1M29 groups compared NMDA and microRNA-29b group(P<0.05),while TGF-β2 were significantly decreased in both microRNA-29b and P1M29 groups compared NMDA and Prominin-1 group(P<0.05).Western blot results showed that both Prominin-1 and P1M29 groups significantly increased the phosphorylation levels of AKT and ERK compared to NMDA and microRNA-29b groups(P<0.05).Flow cytometry analysis revealed that P1M29 could prevent RGC-5 cell apoptosis in the early stage of apoptosis,while immunofluorescence results sho

关键词： Prominin-1 microRNA-29b vascular endothelial growth factor transforming growth factor-β2

Potential plausible role of Wharton’s jelly mesenchymal stem cells for diabetic bone regeneration

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World Journal of Stem Cells 2024年第8期16卷 824-826页

作者： Sheng Zheng Guan-Yu Hu jun-hua li Yi-Kai li Department of Traditional Chinese Orthopedics and Traumatology Center for Orthopedic SurgeryThe Third Affiliated Hospital of Southern Medical UniversityGuangzhou 510630Guangdong ProvinceChina School of Traditional Chinese Medicine Southern Medical UniversityGuangzhou 510515Guangdong ProvinceChina

This letter addresses the review titled“Wharton’s jelly mesenchymal stem cells:Future regenerative medicine for clinical applications in mitigation of radiation injury”.The review highlights the regenerative potential of Wharton’s jelly mesenchymal stem cells(WJ-MSCs)and describes why WJ-MSCs will become one of the most probable stem cells for future regenerative *** potential plausible role of WJ-MSCs for diabetic bone regeneration should be noticeable,which will provide a new strategy for improving bone regeneration under diabetic conditions.

关键词： Wharton’s jelly mesenchymal stem cells Vascular endothelial growth factor Osteogenesis Angiogenesis Diabetic bone regeneration

Designed synthesis of cobalt-oxide-based nanomaterials for superior electrochemical energy storage devices

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Nano Research 2015年第2期8卷 321-339页

作者： hua-jun Qiu li liu Yan-Ping Mu Hui-Juan Zhang Yu Wang School of Chemistry and Chemical Engineering Changqing University Chongqing 400044 China

Cobalt oxides, such as C0304 and CoO, have received increasing attention as potential anode materials for rechargeable lithium-ion batteries （liBs） owing to their high theoretical capacity. Nanostructure engineering has been demonstrated as an effective approach to improve the electrochemical performance of electrode materials for liBs. In this review, we summarize recent developments in the rational design and fabrication of various cobalt oxide-based nanomaterials and their lithium storage performance, including 1D nanowires/belts, 2D nanosheets, 3D hollow/hierarchical structures, hybrid nanostructures with carbon （amorphous carbon, carbon nanotubes and graphene） and mixed metal oxides. By focusing on the effects of their structure on their electrochemical performance, effective strategies for the fabrication of cobalt oxide/carbon hybrid nanostructures are highlighted. This review shows that by rational design, such cobalt-oxide-based nanornaterials are very promising as next generation liB anodes.

关键词： lithium ion battery hybrid peapod structure graphene