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The angucylines are a family of aromatic polyketides featuring a tetracyclic benz[a]anthraquinone skeleton. This class of polycyclic aromatic polyketides are exclusively associated with actinomycetes and can undergo many modifications such as oxidation, ring cleavage, glycosylation and dimerization. Here we report the discovery of a new ether-linked benz[a]anthraquinone heterodimer, named mycolatone (1), from a grasshopper-derived actinomycete, Amycolatopsis sp. HCa1. The structure of mycolatone (1) was determined by comprehensive two-dimensional NMR analysis, high-resolution electrospray ionization mass spectrometry and biogenetic consideration. This new heterodimeric molecule is structurally derived from the dimerization of two tetracyclic angucylines, 2-hydroxy-5-O-methyltetragomycin and PD116779, through an ether bond between C-8 and C-8'. This new structural feature enrich the structural diversity of angucylines. Additionally, the surface tension activity and cytotoxic activities of 1 against human cervical cancer cell line (Hela), human gastric adenocarcinoma cell line (SGC-7901) and human lung adenocarcinoma cell line (SPC-A-1) were evaluated.

In this study, commercial FCD700 ductile irons are austenitized in the intercritical region to observe their effects upon the microstructures and mechanical properties of austempered ductile irons (ADIs). The austenitizing temperature is chosen such that ferrite, austensite, and graphite coexist in the microstructures. Strength of 974 MPa, 16.4% elongation, and impact energy of 166 J are achieved by the ADI austenitized at 1103 K and subsequently austemperted at 673 K. These properties are in contrast to 790 MPa strength, 8.2% elongation, and 42 J impact energy in as-cast FCD700. The properties are also superior to the traditionally austempered ductile iron with 967 MPa strength, 12.7% elongation, and 124 J impact energy. Combinations of the optimum ductility and strength are achieved by 8–19% of proeutectoid ferrite and over 20% of retained austenite in the intercritically treated microstructures. Nanoscale twinned and lenticular martensite forms within the micro-size blocky retained austentite islands during plastic deformation leading to the transformation induced plasticity. The intercritically austenitizing and austempering treatments provide unique combination of strength and elongation for commercial ductile irons.

The title salt, C18H46N2O2Si22+·2Cl−, has been synthesized by reaction ofN,N′-bis(2-hydroxyethyl)ethylenediamine withtert-butyldimethylsilyl chloride. The zigzag backbone dication is located across an inversion centre and the two chloride anions are related by inversion symmetry. The ionic components form a supramolecular two-dimensional networkviaN—H...Cl hydrogen bonding, which is responsible for the high melting point compared with the oily compoundN,N′-bis[2-(tert-butyldimethylsiloxy)ethyl]ethylenediamine.

Xylooligosaccharides (XO), derived from the alkaline (NaOH) extractant of Mikania micrantha, were produced using multiple staged membrane separation and enzymatic xylanolysis. Staged nanofiltration (NMX), ultrafiltration (EUMX), and centrifugation (EMX) processes for the ethanol precipitates were conducted. NMX recovered 97.26% of total xylose and removed 73.18% of sodium ions. Concentrations of total xylose were raised from 10.98 to 51.85 mg/mL by the NMX process. Recovered xylan-containing solids were hydrolyzed by the recombinant Paenibacillus xylanase. 68% XO conversions from total xylose of NMX was achieved in 24 hours. Xylopentaose (DP 5) was the major product from NMX and EMX hydrolysis. Xylohexaose (DP 6) was the major product from EUMX hydrolysis. Results of the present study suggest the applicability for XO production by nanofiltration, as NMX gave higher XO yields compared to those from a conventional ethanol-related lignocellulosic waste conversion process.

Double patterning lithography is extensively used to increase the half-pitch resolution. If there is no enough space to insert a stitch for the un-decomposable pattern, a native conflict is generated. A layout with native conflicts will result in layout modification. The current researches focus on reducing the numbers of stitches and native conflicts in the post-layout or detailed routing stages. In this paper, we propose a track routing algorithm to avoid native conflicts and predict the traces of detailed routing. Experimental results show that the proposed method not only minimizes the number of native conflicts significantly, but also reduces wirelength.

As IC process geometries scale down to the nanometer era, the industry faces severe challenges of manufacturing limitations. For the imperfect manufacturing process, physical design for manufacturability has played an essential role in resolution and thus yield enhancement to guarantee yield. In this paper, we introduce three major challenges arising from the nanometer process technology and survey major existing techniques for handling the challenges in physical design for manufacturability.

Through the literature search, the paper summarizes the experience of information capacity training of European and other developed countries. Combining the fact that information awareness of college students in China is not strong and the actual information capacity is not high, the paper looks for the existing problems and shortcomings, and conducts in-depth analysis and discussion. On this basis, countermeasures and suggestions of the process of designing and building model are put forward to help train information capacity of college students.

In this paper, complementary Huffman encoding techniques are proposed for test data compression of complex SOC designs during manufacturing testing. The correlations of blocks of bits in a test data set are exploited such that more blocks can share the same codeword. Therefore, beside the compatible blocks used in previous works, the complementary property betweens blocks can also be used. Based on this property, two methods are proposed for Huffman encoding. According to this technique, more blocks will share the same codeword and the size of the Huffman tree can be reduced. This will not only reduce the area overhead of the decoding circuitry but also substantially increase the compression ratio. In order to facilitate the proposed complementary encoding techniques, a don't-care assignment algorithm is also proposed. According to experimental results, the area overhead of the decompression circuit is lower than that of the full Huffman coding technique. Moreover, the compression ratio is higher that that of the selective and optimal selective Huffman coding techniques.