As grammatical words, conjunction and relative pronoun play a similar role. They join clauses, phrases, and even words. The terms independent and dependent clauses have become popular for quite a long time. When the c...As grammatical words, conjunction and relative pronoun play a similar role. They join clauses, phrases, and even words. The terms independent and dependent clauses have become popular for quite a long time. When the concept of clause and sentence meets at the presence of NP （Noun Phrase） and VP （Verb Phrase）, there is a right to consider construction as an S or a sentence leaving the conjunction and relative pronoun as means of uniting device and leaving every NP-VP construction as equal units. By employing an embedding theory, we can see hidden parts of a sentence and their roles in other sentences. This article tries to see if it is still necessary to distinguish between dependent and independent clauses.展开更多
Semi-empirical AMI method was used to study 1：1 and 1：2 hydrogen bond complexes formed with perylene dianhydride and pyridine derivatives. The weak interaction energy become bigger as the number of hydrogen bonds in...Semi-empirical AMI method was used to study 1：1 and 1：2 hydrogen bond complexes formed with perylene dianhydride and pyridine derivatives. The weak interaction energy become bigger as the number of hydrogen bonds increases. The donor groups on the host and electron-withdrawing groups on the guest molecules favor hydrogen bonding interactions, and the formation of hydrogen bonding leads to electron density flow from the host to the guest molecules. Electronic spectra of these complexes were computed using INDO/SCI method. Blue-shift of the clectronic absorption spectra for the complexes, comparing that of the host, takes place, and the first peaks for different complexes changed slightly. These are in agreement with the experimcntal results. The cause of blue-shift was discussed, and the electronic transitions were assigned based on theoretical calculations. The potential curve of double proton transfer in the complex was calculated, and the transition state and activated energy relative to the N H bond were obtained.展开更多
Overset or Chimera grid approach is one of methods to cope with complex geometries. A spline based overset grid assembling system has been developed. The system is based on structured grid approach and covers comprehe...Overset or Chimera grid approach is one of methods to cope with complex geometries. A spline based overset grid assembling system has been developed. The system is based on structured grid approach and covers comprehensive features for overset assembling, i.e., grid generation, grid modification, and computing Domain Connectivity Information （DCI） for overset interpolation. Ferguson spline curve is used to compute curves through grid points and cell centers for trimming grids and computing DCI robustly and accurately. Flow simulation around Kriso Container Ship （KCS） with jointed grids shows good continuity of flow field between the grids. The overset grid assembling is enhanced to unsteady problem as dynamic overset approach coupled with a solver which also has been developed in National Maritime Research Institute, Japan. Computed results for pitchup spheroid are compared with measured data and show good agreement in unsteady force acting on the spheroid. It is confirmed that the system has capability to simulate flow field around jointed grids and unsteady flow with dynamic overset assembling approach practically.展开更多
Amphiphilic dendritic poly（glutarnic acid）-b-polyphenylalanine copolymers were synthesized using generation 3 dendritic poly（glutamic acid） as the macroinitiator in the ring-opening polymerization of NCA-Phe. The ...Amphiphilic dendritic poly（glutarnic acid）-b-polyphenylalanine copolymers were synthesized using generation 3 dendritic poly（glutamic acid） as the macroinitiator in the ring-opening polymerization of NCA-Phe. The block copolymers self-assembled micelles with polyphenylalanine segments as core and dendritic poly（glutamic acid） segments as shell. The biocompatibility of the micelles was studied. The release of the anticancer drug doxorubicin from the micelles was investigated in vitro. The results showed that the sustaining release of the drug could last for 60 h. The micellar drug release system was efficient in inhibiting the proliferation of HepG2 liver cancer cells, 75% cancer cells were killed under appropriate in vitro incubation.展开更多
Carbon nanotube (CNT) is one of the most extensively investigated nanomaterials. Patterning soft matter such as liquid crystals and polymers on CNTs could potentially enable various applications for CNTs. We have demo...Carbon nanotube (CNT) is one of the most extensively investigated nanomaterials. Patterning soft matter such as liquid crystals and polymers on CNTs could potentially enable various applications for CNTs. We have demonstrated that controlled polymer crystallization using CNTs as the 1D nucleation sites can lead to periodically functionalized CNTs. Here we show that selected crystalline block copolymers can be periodically decorated along CNTs. This facile technique opens a gateway to periodic patterning on 1-D nanomaterials.展开更多
A kind of amphiphilic rod-coil diblock copolymer consisting both of tetraaniline(TAni)and polyethylene glycol(PEG)blocks,TAni-b-PEG,was synthesized.The diblock copolymer shows excellent electrochromic properties,espec...A kind of amphiphilic rod-coil diblock copolymer consisting both of tetraaniline(TAni)and polyethylene glycol(PEG)blocks,TAni-b-PEG,was synthesized.The diblock copolymer shows excellent electrochromic properties,especially,in switching time and coloration efficiency compared with tetraaniline.TAni-b-PEG is able to self-assemble into spherical structure,which is attributed to the formation of conducting channels and increase of ion-exchange capacity of TAni-b-PEG,implying that a block copolymer with electrochromic block and high ionic conductive block simultaneously possesses improving electrochromic properties.展开更多
文摘As grammatical words, conjunction and relative pronoun play a similar role. They join clauses, phrases, and even words. The terms independent and dependent clauses have become popular for quite a long time. When the concept of clause and sentence meets at the presence of NP （Noun Phrase） and VP （Verb Phrase）, there is a right to consider construction as an S or a sentence leaving the conjunction and relative pronoun as means of uniting device and leaving every NP-VP construction as equal units. By employing an embedding theory, we can see hidden parts of a sentence and their roles in other sentences. This article tries to see if it is still necessary to distinguish between dependent and independent clauses.
文摘Semi-empirical AMI method was used to study 1：1 and 1：2 hydrogen bond complexes formed with perylene dianhydride and pyridine derivatives. The weak interaction energy become bigger as the number of hydrogen bonds increases. The donor groups on the host and electron-withdrawing groups on the guest molecules favor hydrogen bonding interactions, and the formation of hydrogen bonding leads to electron density flow from the host to the guest molecules. Electronic spectra of these complexes were computed using INDO/SCI method. Blue-shift of the clectronic absorption spectra for the complexes, comparing that of the host, takes place, and the first peaks for different complexes changed slightly. These are in agreement with the experimcntal results. The cause of blue-shift was discussed, and the electronic transitions were assigned based on theoretical calculations. The potential curve of double proton transfer in the complex was calculated, and the transition state and activated energy relative to the N H bond were obtained.
文摘Overset or Chimera grid approach is one of methods to cope with complex geometries. A spline based overset grid assembling system has been developed. The system is based on structured grid approach and covers comprehensive features for overset assembling, i.e., grid generation, grid modification, and computing Domain Connectivity Information （DCI） for overset interpolation. Ferguson spline curve is used to compute curves through grid points and cell centers for trimming grids and computing DCI robustly and accurately. Flow simulation around Kriso Container Ship （KCS） with jointed grids shows good continuity of flow field between the grids. The overset grid assembling is enhanced to unsteady problem as dynamic overset approach coupled with a solver which also has been developed in National Maritime Research Institute, Japan. Computed results for pitchup spheroid are compared with measured data and show good agreement in unsteady force acting on the spheroid. It is confirmed that the system has capability to simulate flow field around jointed grids and unsteady flow with dynamic overset assembling approach practically.
基金supported by the National Basic Research Program of China (973 Program,2011CB606206)National High-Tech Research & Development Program of China (863 Program,2007AA021801)+2 种基金National Natural Science Foundation of China (50633020 & 50830105)Sichuan Youth Science & Technology Foundation (07ZQ026-013)Open Fund of Engineering Research Center of Biomass Materials,Ministry of Education (2010LF4002)
文摘Amphiphilic dendritic poly（glutarnic acid）-b-polyphenylalanine copolymers were synthesized using generation 3 dendritic poly（glutamic acid） as the macroinitiator in the ring-opening polymerization of NCA-Phe. The block copolymers self-assembled micelles with polyphenylalanine segments as core and dendritic poly（glutamic acid） segments as shell. The biocompatibility of the micelles was studied. The release of the anticancer drug doxorubicin from the micelles was investigated in vitro. The results showed that the sustaining release of the drug could last for 60 h. The micellar drug release system was efficient in inhibiting the proliferation of HepG2 liver cancer cells, 75% cancer cells were killed under appropriate in vitro incubation.
基金supported by the National Natural Science Foundation of China (DMR-0804838)
文摘Carbon nanotube (CNT) is one of the most extensively investigated nanomaterials. Patterning soft matter such as liquid crystals and polymers on CNTs could potentially enable various applications for CNTs. We have demonstrated that controlled polymer crystallization using CNTs as the 1D nucleation sites can lead to periodically functionalized CNTs. Here we show that selected crystalline block copolymers can be periodically decorated along CNTs. This facile technique opens a gateway to periodic patterning on 1-D nanomaterials.
基金the National Natural Science Foundation of China(21174009,21574003)
文摘A kind of amphiphilic rod-coil diblock copolymer consisting both of tetraaniline(TAni)and polyethylene glycol(PEG)blocks,TAni-b-PEG,was synthesized.The diblock copolymer shows excellent electrochromic properties,especially,in switching time and coloration efficiency compared with tetraaniline.TAni-b-PEG is able to self-assemble into spherical structure,which is attributed to the formation of conducting channels and increase of ion-exchange capacity of TAni-b-PEG,implying that a block copolymer with electrochromic block and high ionic conductive block simultaneously possesses improving electrochromic properties.
