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991.
Four Fe—CO states with 3dσ-4s, 3dδ-3dδ electrons spin-paired or spinunpaired were examined to investigate the influences of pairing versus unpairing mechanisms upon the bonding, interaction in Fe—CO. The calculation results show that the Fe—CO bonding, interaction are determined by a balance between the bonding stabilization, the exchange stabilization with 3dσ-4s electron spinpairing or without it. The 3dδ-3dδ electron spinpairing versus unpairing has a surprised effect on the Fe—CO bonding properties even though the 3dδ orbitals are usually considered as non bonding ones. 相似文献
992.
废弃生物质在超临界水中转化制氢过程的研究 总被引:14,自引:3,他引:14
以废弃生物质转化为富氢气体为目的,使用间歇式超临界水反应器,在反应温度773 K~923 K、压力15.5 MPa~34.5 MPa停留时间1 min~30 min和Ca/C摩尔比0~0.56范围内,对木屑在超临界水条件下生成的气体组成及产率进行了考察。实验表明,Ca/C摩尔比和温度对木屑转化的影响较大。当Ca/C摩尔比为0.48时,碳的气体转化率和氢气产率提高了近一倍。温度从773 K提高到923 K,碳的气体转化率由47%提高到76%,氢气产率由4.5 mmol/g上升到6.9 mmol/g。与温度相比,停留时间和压力的影响不大。 相似文献
993.
994.
995.
Pumping through Porous Hydrophobic/Oleophilic Materials: An Alternative Technology for Oil Spill Remediation 下载免费PDF全文
Jin Ge Yin‐Dong Ye Hong‐Bin Yao Xi Zhu Xu Wang Liang Wu Jin‐Long Wang Prof. Hang Ding Prof. Ni Yong Prof. Ling‐Hui He Prof. Dr. Shu‐Hong Yu 《Angewandte Chemie (International ed. in English)》2014,53(14):3612-3616
Recently, porous hydrophobic/oleophilic materials (PHOMs) have been shown to be the most promising candidates for cleaning up oil spills; however, due to their limited absorption capacity, a large quantity of PHOMs would be consumed in oil spill remediation, causing serious economic problems. In addition, the complicated and time‐consuming process of oil recovery from these sorbents is also an obstacle to their practical application. To solve the above problems, we apply external pumping on PHOMs to realize the continuous collection of oil spills in situ from the water surface with high speed and efficiency. Based on this novel design, oil/water separation and oil collection can be simultaneously achieved in the remediation of oil spills, and the oil sorption capacity is no longer limited to the volume and weight of the sorption material. This novel external pumping technique may bring PHOMs a step closer to practical application in oil spill remediation. 相似文献
996.
Immuno‐Chemotherapeutic Platinum(IV) Prodrugs of Cisplatin as Multimodal Anticancer Agents 下载免费PDF全文
Daniel Yuan Qiang Wong Charmian Hui Fang Yeo Prof. Wee Han Ang 《Angewandte Chemie (International ed. in English)》2014,53(26):6752-6756
There is growing consensus that the clinical therapeutic efficacy of some chemotherapeutic agents depends on their off‐target immune‐modulating effects. Pt anticancer drugs have previously been identified to be potent immunomodulators of both the innate and the adaptive immune system. Nevertheless, there has been little development in the rational design of Pt‐based chemotherapeutic agents to exploit their immune‐activating capabilities. The FPR1/2 formyl peptide receptors are highly expressed in immune cells, as well as in many metastatic cancers. Herein, we report a rationally designed multimodal PtIV prodrug containing a FPR1/2‐targeting peptide that combines chemotherapy with immunotherapy to achieve therapeutic synergy and demonstrate the feasibility of this approach. 相似文献
997.
采用稳态荧光、瞬态荧光及量子化学计算等手段对2-(2-氨基苯基)苯并噻唑(APBT)在不同溶剂中的质子转移进行了研究。结果表明,溶剂的极性及质子化对APBT的质子转移有较大的影响,通过对超分子作用的考察,发现七元瓜环(CB[7])的加入对APBT质子转移起到了一定的抑制作用, APBT与CB[7]能形成化学计量比为1:1的主客体包合物,同时测定了包合物的结合常数等热力学参数。此外,核磁共振氢谱和包合物的理论计算表明APBT分子进入了CB[7]的疏水空腔。 相似文献
998.
Electrochemical Biosensor Based on Bienzyme and Carbon Nanotubes Incorporated into an Os‐complex Thin Film for Continuous Glucose Detection in Human Saliva 下载免费PDF全文
Saliva opens a door for noninvasive and painless glucose testing since it reflects changes in the body physiology of diabetic individuals as compared to healthy ones. In this paper, a unique, disposable saliva biosensor has been developed for accurate, low cost, and continuous glucose monitoring. The biosensor exhibits linear dependence of the catalytic current upon glucose bulk concentration over the 0.05–1.5 mM range (R=0.998). A detection limit of 0.003 mM can be calculated considering three times the standard deviation of the blank signal divided by the sensitivity of the sensor. The selectivity of the biosensor was evaluated by adding the interferent species of lactate, ascorbic acid and uric acid into in 0.5 mM glucose; the nearly negligible interference current indicates its good selectivity. The operational stability of the biosensor was measured in 1 mM glucose over a 2 h period (RSD=3.27 %). A clinical trial on real‐time noninvasive salivary glucose monitoring was carried out on 30 individuals by measuring subjects’ salivary glucose and blood glucose in parallel. The results show that there is a good correlation of glucose levels in saliva and in blood 2 h after breakfast. Thus, the disposable biosensor would be a potential alternative for continuous glucose detection in human saliva. 相似文献
999.
Synthesis and Characterization of Copper(II)–Phosphonate Coordination Chain Array of Metallocages 下载免费PDF全文
Reaction of CuCl2 ·2H2O and 2,4,6‐tris(phosphorylmethyl)mesitylene (H6tpmm) in H2O?DMF solution at room temperature afforded green crystals of [Cu6(H2tpmm)3(H2O)9]·3H2O ( 1 ), which were characterized by Fourier transform infrared (FT‐IR), thermogravimetric (TG) analysis, and powder X‐ray diffraction (PXRD). The solid‐state structure of 1 reveals a one‐dimensional chain array of M4L2 ‐metallocages constituted by the connection of two kinds of metallocage units, namely MC‐A (phosphonate/water‐bridged) and MC‐B (phosphonate‐bridged only), via μ2‐O(phosphonate)? Cu bonds in ABAABA order. The tris‐phosphonate ligand H6tpmm is partially deprotonated to form H2tpmm4?, which displays a cis,cis,cis conformation to bridge six Cu(II) centers via two monodentate phosphonate groups in a η 0:η 0:η 1‐bonding mode and one tridentate phosphonate group in a μ4, η 1:η 1:η 2‐bondingng mode. 相似文献
1000.
Youming Zhang Junxia Su Qiao Li Wenting Li Guoyan Liang Hui Li Haixia Ma Qi Lin Hong Yao Taibao Wei 《中国化学》2016,34(12):1263-1267
Novel fluorescent chemosensor with good selectivity for F? anion was designed and synthesized. The sensor has a bearing on a single functionalized pillar[5]arene and Fe3+ metal complex (PN‐Fe), which showed prominent fluorescent response for F? anion over other common anions (Cl?, Br?, I?, AcO?, HSO4?, H2PO4?, ClO4?, CN? and SCN?). These results were evaluated by fluorescent method. The detection limit of PN‐Fe to F? was calculated to be 2.50×10?7 mol/L. Moreover, the sensor PN‐Fe3+ might serve as a recyclable component in sensing materials. 相似文献