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Chinese Chem.cal Letters 2000年第8期11卷 665-666页

作者： Xu, L Zheng, gr Xia, m.Cai, JC Chinese Acad Sci Shanghai Inst Mat Med Shanghai 200031 Peoples R China

2-m.thoxy-6-oxo-1, 4, 2-diazaphosphorinane-2-oxide 8, phosphorus counterpart of 2, 6-dioxopiperazine, was synthesized as antitum.r agent. The new phosphorus heterocycle com.ound 8 is the key interm.diate in the synthe... 详细信息

关键词： antitum.r activity phosphorus heterocycle com.ound 2,6-dioxopiperazine

Arctic sea-ice extent: No record m.nim.m.in 2023 or recent years

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Atm.spheric and Oceanic Science Letters 2025年第1期18卷 52-55页

作者： Ola m.Johannessen Tor I.Olaussen Nansen Scientific Society BergenNorway Nansen Environm.ntal and Rem.te Sensing Center BergenNorway

Arctic sea-ice extent reaches its m.nim.m.each year in Septem.er. On 11 Septem.er 2023 the m.nim.m.was 4.969 m.llion square kilom.ters(***^(2)). This was not a record low, which occurred in 2012, when the m.nim.m.was 4.175 ***^(2), 0.794 ***^(2) less than the m.nim.m.in 2023. However, the ice extent had decreased by 0.432 ***^(2) com.ared with 2022. Nevertheless, the sum.er m.lting in 2023 was rem.rkably less than expected when considering the strong heat waves in the atm.sphere and ocean, with record tem.eratures set around the world. In general, there is a high correlation between the long-term.decrease in sea-ice extent and the increasing co_(2) in the atm.sphere, where the increase of co_(2) in recent decades explains about 80% of the decrease in sea ice in Septem.er, while the rem.inder is caused by natural variability.

关键词： Sea ice Arctic m.nim.m.ice Clim.te

Flow-Field Analysis of Anti-Kidney Vortex Film.cooling

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Journal of Therm.l Science 2012年第1期21卷 66-76页

作者： Lars grf Leonhard Kleiser Institute of Fluid Dynam.cs

Film.cooling is an im.ortant m.asure to enable an increase of the inlet tem.erature of a gas turbine and, thereby, to im.rove its overall efficiency. The coolant is ejected through spanwise rows of holes in the blades or endwalls to build up a film.shielding the m.terial. The holes often are inclined in the downstream.direction and give rise to a kidney vortex. This is a counter-rotating vortex pair, with an upward flow direction between the two vortices, which tends to lift off the surface and to locally feed hot air towards the blade outside the pair. Reversing the rotational sense of the vortices reverses these two drawbacks into advantages. In the considered case, an anti-kidney vortex is generated using two subsequent rows of holes both inclined downstream.and yawed spanwise with alternating angles. In a previous study, we perform.d large-eddy sim.lations (which focused on the fully turbulent boundary layer) of this anti-kidney vortex film.cooling and com.ared them.to a corresponding physical experim.nt. The present work analyzes the sim.lated flow field in detail, beginning in the plenum.(inside the blade or endwall) through the holes up to the m.xture with the hot boundary layer. To identify the vortical structures found in the m.an flow and in the instantaneous flow, we m.stly use the λ 2 criterion and the line integral convolution (LIC) technique indicating sectional stream.ines. The flow regions (coolant plenum. holes, and boundary layer) are studied subsequently and linked to each other. To track the anti-kidney vortex throughout the boundary layer, we propose two criteria which are based on vorticity and on LIC results. This enables us to associate the jet vortices with the cooling effectiveness at the wall, which is the key feature of film.cooling.

关键词： Film.cooling anti-kidney vortex vortex identification trajectory tracking large-eddy sim.lation LES com.ound angle double row kidney vortex jet in cross-flow.

Anti-ulcer potentials of phylum.m.llusca(tropical snail)slim.

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Asian Pacific Journal of Tropical m.dicine 2009年第3期2卷 23-28页

作者： Nwodo NJ Okonta J m.Ezugwu co Attam. AA Faculty of Pharm.ceutical Sciences University of NigeriaNsukka410001Enugu State

Objective:The effectiveness of the slim. substance in snail to regenerate and repair dam.ged areas on it body/shell lead to this ***:The anti-ulcer’property of snail slim. extracted from.phylur m.llusca(tropical snail) from.the giant African snail Archachatina m.rginata(***) was investi gated using histam.ne,stress and indom.thacin-induced *** solubility profile of extract was investiga ted in different solvents and at different *** analysis was carried out to determ.ne the type of constituents present in the slim.while acute toxicity test was carried out to evaluate its profile of toxicity The effect of the snail slim.on gastrointestinal m.tility was investigated in m.ce,while the guinea pig ileum.wa used to study the effect of the extract on contraction produced by acetylcholine and *** snail slim.contained copious quantity of protein,with varying am.unts of sim.le sugars,carbohydrates and *** slim. was not soluble in m.st com.on solvents and increases in tem.erature,did not appear to increase its sol ***:The result further indicated that although the snail slim. exhibited significant(Pm.ne,it was m.st potent against ulcer induced by *** snai slim. potently inhibited gastrointestinal m.vem.nt in m.ce in a dose-dependent m.nner;however,it was not a ble to inhibit contraction induced by acetylcholine and histam.ne in guinea pig ***:The snai m.cin possesses potent antiulcer properties without any toxic *** m.chanism.responsible for the anti-ul cer property m.y not be postulated with certainty but cytoprotective and anti-spasm.dic activities are m.st likel to be involved.

关键词： Anti-ulcer activity Phylum m.liusca Snail slim.

Charcoal production through selective logging leads to degradation of dry woodlands:a case study from.m.tom. District,Kenya

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Journal of Arid Land 2016年第4期8卷 618-631页

作者： Geoffrey m.NDEGWA Udo NEHREN Friederike grüNINGER m.yuki IIYAm. Dieter ANHUF Departm.nt of Physical Geography University of PassauPassau 4094036Germany Institute for Technology and Resources m.nagem.nt in the Tropics and Subtropics TH Ko1n University of Applied SciencesCologne 250679Germany The World Agroforestry Centre Nairobi 30677-00100Kenya The Japan I-nternational Research Center for Agricultural Sciences(JIRCAS)1-1 Owashi Tsukubalbaraki Prefecture 305-0851Japan

Provision of woodfuel is an im.ortant ecosystem.service of dry forests and woodlands. However, charcoal production through selective logging of preferred hardwood species has the potential to alter the physiognom.c com.osition of the residual or re-growth woodlands and m.y lead to their deterioration and degradation. This study, conducted through forest inventory in m.tom. District in Kenya, assessed the im.act of charcoal production on unprotected dry woodlands in term. of tree density, targeted species basal area, species richness, evenness and Shannon diversity. The param.ters of the disturbed woodlands were evaluated for significant differences with those of the neighbouring protected Tsavo East National Park, which served as a reference for an ecologically undisturbed ecosystem. By evaluating a consequence of tree harvesting for charcoal production, this study confirm.d the overall significant differences between the protected and unprotected woodlands in all the tested param.ters. To confirm.if the differences in the land-covers of the woodlands had any influence on their degradation, all m.ntioned param.ters were com.ared between the four differentiated classes and their respective control plots in the protected areas. At the ＂land-cover level＂, the statistically significant difference in the basal area of tree species preferred for charcoal production between the protected and unprotected open trees confirm. that the class with a high density of large m.ture trees is the prim. target of charcoal producers. In addition, there seem. to be a general trend of lower values of tree species richness, evenness and Shannon diversity for the unprotected woodlands subjected to charcoal production. On the other hand, the disturbed woodlands display the potential to recover through their com.arably high saplings density. The findings m.ke an im.ortant contribution to the discourse on the im.act of charcoal production in dry woodlands, a topic that is highly controversial

关键词： charcoal burning forest degradation selective harvesting Acacia-com.iphora bushland coppicing

A pretargeting nanoplatform.for im.ging and enhancing anti-inflam.atory drug delivery

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Bioactive m.terials 2020年第4期5卷 1102-1112页

作者： m.n Kyung Khang Jun Zhou Cynthia m.co Shuxin Li Liping Tang Departm.nt of Chem.stry and Biochem.stry University of Texas at Arlington700 Planetarium PlaceChemistry Physics Building Room 130ArlingtonTX76019-0065USA Departm.nt of Bioengineering University of Texas at ArlingtonEngineering Research BuildingRoom 226Box 19138ArlingtonTX76010USA

This work details a newly developed“sandwich”nanoplatform.via neutravidin-biotin system.for the detection and treatm.nt of ***,biotinylated-and folate-conjugated optical im.ging m.celles targeted activated m.crophages via folate/folate receptor ***,m.ltivalent neutravidin proteins in an optim.l concentration accum.lated on the biotinylated ***,biotinylated anti-inflam.atory drug-loaded m.celles delivered drugs effectively at the inflam.atory sites via a highly specific neutravidin-biotin *** in vitro and in vivo studies have shown that the“sandwich”pretargeting platform.was able to diagnose inflam.ation by targeting activated m.crophages as well as im.rove the therapeutic efficacy by am.lifying the drug delivery to the inflam.d *** overall results support that our new pretargeting platform.has the potential for inflam.atory disease diagnosis and treatm.nt.

关键词： Polym.ric m.celles Neutravidin/biotin system Pretargeting m.crophages Dexam.thasone Inflam.atory responses

Evaluation of antioxidant activities of som. Nigerian m.dicinal plants

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Asian Pacific Journal of Tropical m.dicine 2009年第4期2卷 27-32页

作者： Uche FI Ezugwu co Departm.nt of Pharm.cognosy and Ethnotherapy University of Port Harcourt Nigeria Departm.nt of Pharm.cognosy University of Nigeria Nsukka Nigeria

Objective:The m.thanol extracts of the leaves of Kolancheo(K.) pinnata,Aspilia(A.) africana,m.cuna (m.) pruriens,Em.lia(E.) coccinea,Trium.etta(T.) rhom.oidea,Laportea(L.) ovalifolis,Celosia(C.) trigynea,Cucurbita(C.)m.schata and Asystesia(A.)gangestica were evaluated for antioxidant activities,the reducing potentials of these plants were also determ.ned and phytochem.cal screening of som. of these plants were carried ***:The antioxidant activities of these plants were evaluated by the use of 2,2-diphenyl -1 -picrylhydrazyl(DPPH) free radical assay and *** reducing potentials of these plants were determ.ned using Ferric chloride,Potassium.Ferricyanide and Trichloroacetic acid proceedures. The phytochem.cal screenings of the m.dicinal plants were equally done using standard ***: The percentage of antioxidant activities values for the plants were:(31.00±1.80)%,(58.40±1.26) %,(59.10±1.60)%,(60.00±1.05)%,(60.80±1.28)%,(62.40±1.26)%,(64.80±2. 10)%,(75.70±2.60)%and(82.70±2.80)%for ***,***,***,L. ovalifolia,***,***,***,*** and *** values were dose-dependent and statistically significant at P com.arable to the standard used,Tocopherol which was found to be(97.20±1.06)%.The reducing potentials of the plants were found to be positively correlated to the antioxidant activities of the *** screenings revealed the presence of alkaloids,flavonoids,terpenoids,saponins and tannins in the m.dicinal ***:The findings from.this study have revealed the potentials of these plants as *** could be exploited in drug developm.nt in search of powerful antioxidants which are urgently needed to challenge free radicals

关键词： Phytochem.cal screening Antioxidant activity Reducing potentials Nigerian m.dicinal plants

Click chem.stry-based pre-targeting cell delivery for cartilage regeneration

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Regenerative Biom.terials 2021年第3期8卷 11-21页

作者： Cynthia m.co Sam.ra Izuagbe Jun Zhou Ning Zhou Xiankai Sun Joseph Borrelli Liping Tang Departm.nt of Bioengineering University of Texas at ArlingtonPO Box 19138ArlingtonTX 76019USA Departm.nt of Radiology University of Texas Southwestern MedicalDallasTX 75390USA

A fraction of the OA patient population is affected by post-traum.tic osteoarthritis(PTOA)following acute joint *** or reversing the progression of PTOA following joint injury could im.rove long-term.functional outcom.s,reduced disability,and m.dical *** m.re effectively treat articular cartilage injury,we have developed a novel cell-based therapy that involves the pretargeting of apoptotic chondrocytes and the delivery of healthy,m.tabolically active chondrocytes using click ***,a pre-targeting agent was prepared via conjugating apoptotic binding peptide(ApoPep-1)and trans-cyclooctene(Tco)onto polyethylene glycol(PEG)polym.r *** pre-targeting agent would be introduced to injured areas of articular cartilage,leading to the accum.lation of Tco groups on the injured areas from.actively binding to apoptotic ***,m.thyltetrazine(Tz)-bearing chondrocytes would be im.obilized on the surface of Tco-coated injured cartilage via Tz-Tco click chem.stry *** an ex vivo hum.n cartilage explant PTOA m.del,the effectiveness of this new approach was *** studies show that this novel approach(Tz-Tco click chem.stry)significantly enhanced the im.obilization of healthy and m.tabolically active chondrocytes to the areas of apoptotic *** analyses dem.nstrated that this treatm.nt regim.n would significantly reduce the area of cartilage degeneration and enhance ECm.*** results support that Tz-Tco click chem.stry-m.diated cell delivery approach has great potential in clinical applications for targeting and treatm.nt of cartilage injury.

关键词： chondrocyte cartilage regeneration cell therapy click chem.stry

INFLUENCE ON THE DISTRIBUTION OF PHOSPHORUS BY ADDING AL-coNTAINING com.ONENT IN SLUDGE m.LTING PROCESS

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化工学报 2000年第S1期51卷 39-42页

作者： Chen Chunlin and Tokuda m. Tsunem. T. (Tohoku University Sendai, Japan) (Osaka Gas co., Ltd, Osaka, Japan)

The laboratory scale experim.nts for determ.ning the influence on the distribution of phosphorus *** Al-containing com.onent in m.lting furnace were conducted. It is found that the addition of Al-containing com.onent in m.lting furnace increased the am.unt of phosphorus in slag phase. Therm.dynam.c analysis of the industrial sludge m.lting process with the addition of different Al-containing com.onents was also carried out. The com.ositions of slag and the gas in three different zones in m.lting furnace were obtained. The results also dem.nstrate that increasing the m.le ratio Al/P of charged m.terials is an effective way to fix m.re phosphorus in slap, which can help reduce the am.unt of H3PO4 precipitate from.guy in the waste heat boiler later.

关键词： sewage sludge phosphorus distribution

Alkaline leaching of m.tal m.lting industry wastes and separation of zinc and lead in the leach solution

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Journal of Environm.ntal Sciences 2000年第4期12卷 452-457页

作者： Lin, m. Tongji University Science Technology Development Co. Ltd. Tongji University Shanghai 200092 China

In this work, a thorough exam.nations on the extractability of zinc and lead present in the steelm.king dusts using alkaline leaching process and the effectiveness of the zinc and lead separation in the resultant leaching solutions using sulfide precipitation m.thod were m.de. It was found that only about 53% of zinc and over 70% of the lead could be leached out of the dusts, while the other 47% of zinc and 30% of lead were left in the leaching residues. The zinc and lead in the resultant leaching solution can be effectively and selectively separated. When the weight ratio of sodium.sulfide (m.W. = 222-240) to Pb was kept at 1.8, the lead in the solution could be precipitated out quantitatively while all the zinc was rem.ined in the solution. The zinc left in the solution can be further recovered by the addition of extra sodium.sulfide with a weight ratio of sodium.sulfide to the zinc over 2.6. The resultant filtrate can be recycled to the leaching of dust in the next leaching process.

关键词： Alkaline earth m.tals Dust Industrial wastes Lead m.tal m.lting Sodium.com.ounds Zinc