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Quantitative characterization of polyacrylamide–shale interaction under various saline conditions

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Petroleum Science 2017年第3期14卷 586-596页

作者： Samyukta Koteeswaran jack C.Pashin Josh d.Ramsey Peter E.Clark School of Chemical Engineering Oklahoma State UniversityStillwater OK 74078 USA Boone Pickens School of Geology Oklahoma State University Stillwater OK 74078 USA

Interaction of polymer-containing injected fluids with shale is a widely studied phenomenon, but much is still unknown about the interaction of charged polyacrylamides such as anionic and cationic polyacrylamides with shale. The nature of interaction of charged polyacrylamides with shale is not well understood, especially from the perspective of assessing the potential for polyacrylamides to cause formation damage. Zeta potential and rheological measurements were made for Chattanooga and Pride Mountain shales suspended in polyacrylamide solutions with and without inorganic salts and tetramethyl ammonium chloride（TMAC）. The change in zeta potential and viscosity with time was recorded. The magnitude of decrease in the absolute value of zeta potential with time is indicative of adsorption of polymer on the surface of shale and serves as a measure of the extent of polymer interaction with shale. The salts that were used in this study are potassium chloride（KCl）, sodium chloride（Na Cl）. This study quantified the interaction of anionic and cationic polyacrylamide with different North American *** the experimental results, it was determined that the polyacrylamides can interact strongly with shale, particularly the cationic polyacrylamide. The objective of this study was to determine the extent of interaction of anionic and cationic polyacrylamide with each shale sample in the presence of additives such as salts.

关键词： Anionic and cationic polyacrylamides Chattanooga shale Pride Mountain shale Zeta potentialSlurry rheology

ITERATIVE l1 MINIMIZATION FOR NON-CONVEX COMPRESSEd SENSING

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Journal of Computational Mathematics 2017年第4期35卷 439-451页

作者： Penghang Yin jack Xin department of Mathematics University of California Los Angeles CA 90095 USA department of Mathematics University of California Irvine CA 92697 USA

An algorithmic framework, based on the difference of convex functions algorithm （d- CA）, is proposed for minimizing a class of concave sparse metrics for compressed sensing problems. The resulting algorithm iterates a sequence ofl1 minimization problems. An exact sparse recovery theory is established to show that the proposed framework always improves on the basis pursuit （l1 minimization） and inherits robustness from it. Numerical examples on success rates of sparse solution recovery illustrate further that, unlike most existing non-convex compressed sensing solvers in the literature, our method always out- performs basis pursuit, no matter how ill-conditioned the measurement matrix is. Moreover, the iterative l1 （ILl） algorithm lead by a wide margin the state-of-the-art algorithms on l1/2 and logarithimic minimizations in the strongly coherent （highly ill-conditioned） regime, despite the same objective functions. Last but not least, in the application of magnetic resonance imaging （MRI）, IL1 algorithm easily recovers the phantom image with just 7 line projections.

关键词： Compressed sensing Non-convexity difference of convex functions algorithm,Iterative l1 minimization.

Woody plant cell walls:Fundamentals and utilization

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Molecular Plant 2024年第1期17卷 112-140页

作者： Wei Li Ying-Chung Jimmy Lin Ying-Lan Chen Chenguang Zhou Shuang Li Nette de Ridder dyoni M.Oliveira Lanjun Zhange Baocai Zhang jack P.Wang Changzheng Xu Xiaokang Fu Keming Luo Ai-Min Wu Taku demura Meng-Zhu Lu Yihua Zhou Laigeng Li Toshiaki Umezawa Wout Boerjan Vincent L.Chiang State Key Laboratory of Tree Genetics and Breeding Northeast Forestry UniversityHarbin 150040China department of Life Science National Taiwan UniversityTaipeiTaiwanChina department of Biotechnology and Bioindustry Sciences College of Bioscience and BiotechnologyNational Cheng Kung UniversityTainanTaiwanChina department of Plant Biotechnology and Bioinformatics Ghent UniversityTechnologiepark 719052 GhentBelgium VIB Center for Plant Systems Biology Technologiepark 719052 GhentBelgium State Key Laboratory of Plant Genomics Insttute of Genetics and developmental Biology Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Forest Biotechnology Group Department of Forestry and Environmental ResourcesNorth Carolina State UniversityRaleighNC 27695USA Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation Integrative Science Center of Germplasm CreationSchool of Life SciencesSouthwest UniversityChongqing 400715China Guangdong Key Laboratory for Innovative developmentand Utilization of Forest Plant Germplasm College of Forestry and Landscape ArchitecturesSouth China Agricultural UniversityGuangzhou510642China Center for digital Green-innovation Nara Institute of Science and TechnologykomaNara 630-0192Japan State Key Laboratory of Subtropical Siviculture College of Forestry and BiotechnologyZhejang A&F UniversityHangzhou 311300China CAS Center for Excellence in Molecular Plant Sciences Chinese Academy of Sciences300 Fenglin RoadShanghai 200032China Laboratoryof MetabolicScienceofForest Plants and Microorganisms Rsearch Institute for Sustainable HumanosphereKyoto UniversityUjiKyoto 611-0011 Japan

Cell walls in plants,particularly forest trees,are the major carbon sink of the terrestrial *** and biosynthetic features of plant cell walls were revealed early on,focusing mostly on herbaceous model *** developments in genomics,transcriptomics,epigenomics,transgenesis,and associated analytical techniques are enabling novel insights into formation of woody cell ***,we review multilevel regulation of cell wall biosynthesis in forest tree *** highlight current approaches to engineering cell walls as potential feedstock for materials and energy and survey reported field tests of such engineered transgenic *** outline opportunities and challenges in future research to better understand cell type biogenesis for more efficient wood cell wall modification and utilization for biomaterials or for enhanced carbon capture and storage.

关键词： regulation of cell wall formation biosynthesis of cell wall components lignin cellulose hemicellulose cell wall utilization

Problems on Graphs with Fixed Smallest Eigenvalue

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Algebra Colloquium 2020年第1期27卷 51-54页

作者： jack Koolen Qianqian Yang Wen-Tsun Wu Key Laboratory of CAS School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026China School of Mathematical Sciences University of Science and Technology of China Hefei 230026China

In this note we give several problems and conjectures on graphs with fixed smallest eigenvalue.

关键词： 5-integrability lattice graph

Twice Q-polynomial distance-regular graphs of diameter 4

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Science China Mathematics 2015年第12期58卷 2683-2690页

作者： MA JianMin KOOLEN jack H. College of Mathematics & Information Science and Hebei Key Lab of Computational Mathematics & Applications Hebei Normal University School of Mathematical Sciences University of Science and Technology of China

It is known that a distance-regular graph with valency k at least three admits at most two Qpolynomial structures. We show that all distance-regular graphs with diameter four and valency at least three admitting two Q-polynomial structures are either dual bipartite or almost dual bipartite. By the work of dickie(1995) this implies that any distance-regular graph with diameter d at least four and valency at least three admitting two Q-polynomial structures is, provided it is not a Hadamard graph, either the cube H(d, 2)with d even, the half cube 1/2H(2d + 1, 2), the folded cube?H(2d + 1, 2), or the dual polar graph on [2A2d-1(q)]with q 2 a prime power.

关键词： distance-regular graph P-or Q-polynomial structure tight

Transplacental induction of fatty acid oxidation in term fetal pigs by the peroxisome proliferator-activated receptor alpha agonist clofibrate

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Journal of Animal Science and Biotechnology 2016年第3期7卷 341-352页

作者： Xi Lin Sheila Jacobi jack Odle Laboratory of developmental Nutrition Department of Animal SciencesNorth Carolina State University

Background： To induce peroxisomal proliferator-activated receptor α（PPARα） expression and increase milk fat utilization in pigs at birth, the effect of maternal feeding of the PPARα agonist, clofibrate（2-（4-chlorophenoxy）-2-methyl-propanoic acid, ethyl ester）, on fatty acid oxidation was examined at ful-term delivery（0 h） and 24 h after delivery in this *** group of pigs（n = 10） was delivered from pregnant sows fed a commercial diet with or without 0.8% clofibrate for the last 7 d of gestation. Blood samples were col ected from the utero-ovarian artery of the sows and the umbilical cords of the pigs as they were removed from the sows by C-section on day 113 of ***： HPLC analysis identified that clofibric acid was present in the plasma of the clofibrate-fed sow（~4.2 μg/m L）and its offspring（~1.5 μg/m L）. Furthermore, the maternal-fed clofibrate had no impact on the liver weight of the pigs at 0 h and 24 h, but hepatic fatty acid oxidation examined in fresh homogenates showed that clofibrate increased（P 〈 0.01）^14C-accumulation in CO2 and acid soluble products 2.9-fold from [1-^14C]-oleic acid and 1.6-fold from[1-^14C]-lignoceric acid respectively. Correspondingly, clofibrate increased fetal hepatic carnitine palmitoyltransferase（CPT）and acyl-Co A oxidase（ACO） activities by 36% and 42% over controls（P 〈 0.036）. The m RNA abundance of CPT I was 20-fold higher in pigs exposed to clofibrate（P 〈 0.0001） but no differences were detected for ACO and PPARα m RNA between the two ***： These data demonstrate that dietary clofibrate is absorbed by the sow, crosses the placental membrane, and enters fetal circulation to induce hepatic fatty acid oxidation by increasing the CPT and ACO activities of the newborn.

关键词： Clofibrate Fatty acid oxidation Pigs Placenta transfer

Long-term safety of laser in situ keratomileusis in eyes with thin corneas： 5-year follow-up

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International Journal of Ophthalmology(English edition) 2018年第7期11卷 1227-1233页

作者： Yao-Wen Song Rui He jack X.Ma douglas d.Koch Li Wang Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical University Beijing Ophthalmology and VisualScience Key Laboratory Beijing 100730 China Shanxi Eye Hospital Taiyuan 030002 Shanxi ProvinceChina Mc Govern Medical School University of Texas Health Science Center at Houston TX 75835 USA Cullen Eye Institute Department of Ophthalmology Baylor College of Medicine Houston TX 75844 USA

AIM： To investigate the long term（≥5 y） efficacy, predictability, and safety of laser in situ keratomileusis（LASIK） in eyes with thin corneas [central corneal thickness（CCT）〈500 μm]. METHOdS： A total of 339 patients met the criteria of this study. Finally, 175 eyes of 89 patients who had thin corneas and underwent LASIK≥5 y ago returned to our clinic and included in this study. Preoperative parameters recorded included uncorrected visual acuity（UCVA）, corrected distance visual acuity（CdVA）, manifest refraction, CCT and corneal topography. At returning visits, in addition to visual acuity and manifest refraction, ultrasound CCT and corneal topography were performed. Optical coherence tomography was used to measure the CCT, LASIK flap thickness, and residual stromal bed thickness（RSBT）. Safety index, efficacy index, percentage of eyes within ±0.5 d and ±1.0 d of refraction, percent tissue altered（PTA）, and percentage stromal bed thickness（PSBT） were calculated. RESULTS： The safety index was 1.09 and efficacy index was 0.99. The percentages of eyes within ±0.5 d and ±1.0 d were 71.2% and 87.7%, respectively. The mean PTA was 40%±6%（range 20% to 55%）; 76 eyes（43.4%） had PTA 〈40% and 99 eyes（56.6%） had PTA≥40%. The mean RSBT was 303±27 μm（range 240 to 390 μm）, and 2 eyes had RSBT〈250 μm. The mean PSBT was 61%±9%（range 51% to 85%）. No eyes developed ectasia. CONCLUSION： In this cohort with the PSBT of 50% or more, LASIK is safe with follow-up for at least 5 y.

关键词： LASIK thin cornea long-term safety percent tissue altered percentage stromal bed thickness

Nucleic acid crystallization and X-ray crystallography facilitated by single selenium atom

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Frontiers of Chemical Science and Engineering 2016年第2期10卷 196-202页

作者： Wen Zhang jack W. Szostak Zhen Huang department of Chemistry Georgia State University Atlanta GA 30303 USA Howard Hughes Medical Institute Department of Molecular Biology and Center for Computational and Integrative Biology Massachusetts General Hospital Boston MA 02114 USA College of Life Sciences Sichuan University Chengdu 610041 China

X-ray crystallography is a powerful strategy for 3-d structure determination of macromolecules, such as nucleic acids and protein-nucleic acid complexes. However, the crystallization and phase determination are the major bottle-neck problems in crystallography. Recently we have successfully developed synthesis and strategy of selenium-derivatized nucleic acids （SeNA） for nucleic acid crystallography. SeNA might not only provide the rational strategies to solve the phase determination problem, but also offer a potential strategy to explore crystallization solutions.

关键词： selenium dNA RNA nucleic acid crystallization

Families in Botryosphaeriales:aphylogenetic,morphological and evolutionary perspective

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Fungal diversity 2019年第1期94卷 1-22页

作者： Alan J.L.Phillips Kevin d.Hyde Artur Alves Jian-Kui(jack)Liu Faculdade de Ciencias Biosystems and Integrative Sciences Institute(BioISI)Universidade de LisboaCampo Grande1749-016 LisbonPortugal Center of Excellence in Fungal Research Mae Fah Luang UniversityChiang Rai 57100Thailand departamento de Biologia CESAMUniversidade de Aveiro3810-193 AveiroPortugal Guizhou Institute of Biotechnology Guizhou Academy of Agricultural SciencesGuiyang 550006People’s Republic of China

Botryosphaeriales was introduced in 2006 for a single family *** then the number of families has increased as a result of the transfer of one family(Planistromellaceae)into the order,re-instatement of another(Phyllostictaceae),while others resulted from raising genera to family status(Aplosporellaceae,Endomelanconiopsisaceae,Melanopsaceae,Pseudofusicoccumaceae,Saccharataceae and Septorioideaceae).All these decisions were based solely on phylogenetic analyses of several different *** has been no consensus on which loci are suitable markers at this taxonomic level and in some cases the datasets used to construct the phylogenies were *** this paper,the families of Botryosphaeriales were re-assessed in terms of morphology of the sexual morphs,phylogenetic relationships based on ITS and LSU sequence data,and evolutionary divergence times of lineages in relation to major events in the evolution of their hosts on a geological *** main lineages were resolved in the phylogenetic analyses and these correspond to six groups as defined on morphology of the sexual *** lineages evolved during the Late epoch of the Cretaceous period and survived the catastrophic event that led to the mass extinction of non-avian dinosaurs and a great loss of plant diversity at the end of the Cretaceous *** then diversified during the Paleocene and Eocene epochs of the Paleogene *** six lineages are considered to represent families in ***,six families(Aplosporellaceae,Botryosphaeriaceae,Melanopsaceae,Phyllostictaceae,Planistromellaceae and Saccharataceae)are accepted in Botryosphaeriales,while three(Endomelanconiopsisaceae,Pseudofusicoccumaceae and Septorioideaceae)are reduced to synonymy under existing families.

关键词： Classification dothideomycetes Evolutionary divergence times Morphology