J. Fraser Stoddart

Bio: J. Fraser Stoddart is an academic researcher from Northwestern University. The author has contributed to research in topics: Catenane & Supramolecular chemistry. The author has an hindex of 147, co-authored 1239 publications receiving 96083 citations. Previous affiliations of J. Fraser Stoddart include Zhejiang University & Northwest University (United States).

The Chemistry of the Mechanical Bond

Abstract: The use of templation in the synthesis of unnatural products where two or more components are mechanically interlocked has not only raised the efficiency of their production to near quantitative levels in some instances, but the molecular recognition that aids and abets the templation is also part and parcel of the molecules after they have been prepared, purified and presented for investigation. The fact that the molecular recognition ‘lives on’ in mechanically interlocked molecules, following their templated formation, makes them prime candidates for applications that straddle the scientific and technical worlds from devices that could spawn new information technologies to integrated systems that could have fundamental applications in the health-care industries. The challenge to make more and more sophisticated compounds is predicated upon our fundamental understanding of the nature of the mechanical bond and how this associated knowledge base can be employed to do complex systems chemistry in very different environments where emergent phenomena become the order of the day (critical review, 104 references).

Complex formation between bisparaphenylene-(3n+4)-crown-n ethers and the paraquat and diquat dications

Abstract: U.v. and n.m.r. spectroscopic investigations in solution have been employed to assess the ability of a series (n= 7–12) of bisparaphenylene-(3n+ 4)-crown-n ethers to form stable 1:1 complexes with [Diquat]2+ and [Paraquat]2+ dications; these mappings of molecular recognition are supported by fast atom bombardment mass spectrometry of the 1:1 complexes with both [Diquat][PF6]2 and [Paraquat][PF6]2, and a single crystal X-ray structure analysis of [Diquat·BPP31C9][PF6]2.

Template-directed one-step synthesis of cyclic trimers by ADMET

Abstract: A trifurcated template, containing three secondary dialkylammonium ion recognition sites for encirclement by a dibenzo [24]crown-8-containing acyclic diene, is used to promote acyclic diene metatheses (ADMET) catalyzed by ruthenium−alkylidene complexes, affording a cyclic trimer in 55% yield. Following this one-step, threefold ADMET reaction, the resulting cyclic trimer was isolated by preparative HPLC and characterized by NMR spectroscopy and mass spectrometry.

The Synthesis and Characterization of a New Family of Polyamide Dendrimers

Abstract: An eight-member family of dendrimers has been built up by both convergent and divergent methodologies from an orthogonally-protected amino-tetraacid. Examination of the series by GPC, 1H NMR and computer modeling suggests that the three-directional fourth-generation dendrimer (right) has a globular, void-containing structure.

Fast parallel algorithms for short-range molecular dynamics

Abstract: Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

Gold nanoparticles: assembly, supramolecular chemistry, quantum-size-related properties, and applications toward biology, catalysis, and nanotechnology.

Abstract: Although gold is the subject of one of the most ancient themes of investigation in science, its renaissance now leads to an exponentially increasing number of publications, especially in the context of emerging nanoscience and nanotechnology with nanoparticles and self-assembled monolayers (SAMs). We will limit the present review to gold nanoparticles (AuNPs), also called gold colloids. AuNPs are the most stable metal nanoparticles, and they present fascinating aspects such as their assembly of multiple types involving materials science, the behavior of the individual particles, size-related electronic, magnetic and optical properties (quantum size effect), and their applications to catalysis and biology. Their promises are in these fields as well as in the bottom-up approach of nanotechnology, and they will be key materials and building block in the 21st century. Whereas the extraction of gold started in the 5th millennium B.C. near Varna (Bulgaria) and reached 10 tons per year in Egypt around 1200-1300 B.C. when the marvelous statue of Touthankamon was constructed, it is probable that “soluble” gold appeared around the 5th or 4th century B.C. in Egypt and China. In antiquity, materials were used in an ecological sense for both aesthetic and curative purposes. Colloidal gold was used to make ruby glass 293 Chem. Rev. 2004, 104, 293−346

The Chemistry and Applications of Metal-Organic Frameworks

Abstract: Crystalline metal-organic frameworks (MOFs) are formed by reticular synthesis, which creates strong bonds between inorganic and organic units. Careful selection of MOF constituents can yield crystals of ultrahigh porosity and high thermal and chemical stability. These characteristics allow the interior of MOFs to be chemically altered for use in gas separation, gas storage, and catalysis, among other applications. The precision commonly exercised in their chemical modification and the ability to expand their metrics without changing the underlying topology have not been achieved with other solids. MOFs whose chemical composition and shape of building units can be multiply varied within a particular structure already exist and may lead to materials that offer a synergistic combination of properties.