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Host-guest complexes of cucubit[8]uril with phenanthrolines and some methyl derivatives

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Science China Chemistry 2005年第4期48卷 305-314页

作者： DAY Anthony i Chemistry Discipline School of Physical Environmental and Mathematical SciencesUniversity College UNSWAustralian Defence Force AcademyCanberraACT2600 Australia

The host-guest relationship between cucurbit[8]uril,phenanthrolines and some methyl substituted 1,10-phenanthrolines has been investigated by using 1H NMR spectroscopy and fluorescence *** results showed that phenanthrolines as molecular guests bind in the cavity and portal of cucurbit[8]uril in a ratio of 2:1 (guest to host).The phenanthroline isomers 1,10-,1,7-and 4,7-showed red shifts between 47 and 108 nm and pronounced in-creases in fluorescent *** same isomers produced inclusion complexes with cucur-bit[8]uril which had moderate to fast exchange rates on the 1H NMR time *** methyl substituted 1,10-phenanthrolines studied gave stable inclusion complexes in a ratio of 2:1 which showed slow exchange *** guests formed p-p stacked pairs which were cavity bound but also partly protruded from only one portal forming unsymmetrical host-guest *** addition,these p-p stacked pairs formed orientation isomers within the confines of the cucur-bit[8]uril cavity.

关键词： 1H NMR technique, fluorescence, cucurbituril, phenanthroline, host-guest, orientation isomers.

Characterization of Arithmetic Functions that Preserve the Sum-of-squares Operation

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Acta Mathematica Sinica,English Series 2014年第4期30卷 689-695页

作者： Bojan BAi Department of Mathematics and informatics University of Novi Sad

We characterize all functions f ： N → C such that f（m^2 ＋ n^2） = f（m）^2 ＋ f（n）^2 for all m, n ∈ N. it turns out that all such functions can be grouped into three families, namely f ≡ 0, f（n） = ±n （subject to some restrictions on when the choice of the sign is possible） and f（n） =±l/2（again subject to some restrictions on when the choice of the sign is possible）.

关键词： Arithmetic function functional equation sum of squares

A precise monitoring of snow surface height in the region of Lambert Glacier basin-Amery ice Shelf,East Antarctica

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Science China Earth Sciences 2005年第1期48卷 100-111页

作者： i.Allison Australian Antarctic Division and Antarctic Climate and Ecosystems CRC

The net surface snow accumulation on the Antarctic ice sheet is determined by a combination of precipitation, sublimation and wind redistribution. We present a one-year record of hourly snow-height measurements at LGB69 (70°50'S, 77°04'E, 1850 m a.s.l.). east side of Lambert Glacier basin (LGB), and 4 year record at G3 (70°53'S, 69°52'E, 84 m a.s.l.), Amery ice Shelf (AiS). The measurements were made with ultrasonic sensors mounted on automatic weather stations installed at two sites. The snow accumulation at LGB69 is approximately 70 cm. Throughout the winter, between April and September, there was little change in surface snow height (SSH) at the two sites. The negative SSH change is due to densification at LGB69, and is due to both ablation and densification at G3. The strongest accumulation at two sites occurred during the period between October and March (accounting for 101.6% at LGB69), with four episodic increasing events occurring during 2002 for LGB69, and eight events during 1999-2002 for G3 (2 to 3 events per year). At LGB69, these episodic events coincided with obvious humidity 'pulses' and decreases of incoming solar radiation as recorded by the AWS. Observations of the total cloud amount at Davis station, 160 km NNE of LGB69, showed good correlation with major accumulation events recorded at LGB69. There was an obvious anti-correlation between the lowest cloud height at Davis and the daily accumulation rate at LGB69. Although there was no correlation over the total year between wind speed and accumulation at LGB69, large individual accumulation events are associated with episodes of strong wind (>7 m/s), we estimate drift snow may contribute to total SSH up to 35%. Strong accumulation events at LGB69 are associated with major storms in the region and inland transport of moist air masses from the coast.

关键词： Antarctica, Lambert Glacier basin, Amery ice Shelf, accumulation, katabatic wind.

Single and multi domain buckled germanene phases on Al(111)surface

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Nano Research 2019年第12期12卷 2988-2996页

作者： Dmitriy A.Muzychenko Sergey i.Oreshkin Vladimir i.Panov Chris Van Haesendonck Andrey i.Oreshkin Faculty of Physics Lomonosov Moscow State University119991 MoscowRussia Sternberg Astronomical institute Lomonosov Moscow State University119234 MoscowRussia Solid-State Physics and Magnetism Section KU LeuvenBE-3001 LeuvenBelgium

The simultaneous formati on of single domain(3×3)and multi domai n(√7×√7)R(±19.1°)germa nene phases on Al(111)surface in thesub-monolayer range was studied using seanning tunneling microscopy(STM)and density functional theory(DFT)based *** results revealed that both germa nene phases nu cleate and grow in dependently from each other and regardless of Al substratetemperature within significantly expanded range Ts=27-200℃.Our results unambiguously showed that STM images with hexagonalcontrast yield correct-resolved structure for both germanene phases,while honeycomb contrast is a result of an artificial tip-induced STM ***-principles calculations suggested atomic models with strongly buckled germanene(2×2)/Al(111)(3×3)and(√3×√3)R30°/Al(111)(√7×√7)R(±19.1°)with one of eight and one of six Ge atoms protruding upward respectively,that consistently describe the experimentally observed STM images both for single and multi domai n surface *** to the DFT based simulati ons both germa nene(2×2)and(√3×√3)R30°superstructures have a stretched lattice strain with respect to the ideal free-standing germa nene by 6.2%and 13.9%,***,numerous small domains separated by domain boundaries in the(√3×√3)R30°/Al(111)(√7×√7)R(±19.1°)germanenephase tend to reduce the surface energy and prevent the formation of extended single domains,in contrast to the(2×2)/Al(111)(3×3)***,our experimental results showed that the nucleation and growth of germa nene on Al(111)surface yield strong modifications of Alsurface even at room temperature(RT),which may be contributed to the formation of Al-Ge alloy due to Ge surface solid-states reactivitythat was ignored in recent *** is already evident from our present findings that the role of Al atoms in the formation of(3×3)and(√7×√7)R(±19.1°)germa nene phases is worthy to be carefully studied in the future,which could be an important knowledge for large-quantityfabrication of germane

关键词： germanene two-dimensional(2D)materials scanning tunneling microscopy density functional theory aluminum

On Evaluation of Overlap integrals with Noninteger Principal Quantum Numbers

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Communications in Theoretical Physics 2004年第5X期42卷 753-756页

作者： i.i.Guseinov B.A.Mamedov DepartmentofPhysics FacultyofArtsandSciencesOnsekizMartUniversityCanakkaleTurkey DepartmentofPhysics FacultyofArtsandSciencesGaziosmanpasaUniversityTokatTurkey

By use of complete orthonormal sets of ψα exponential-type orbitals (ψα-ETOs, α = 1, 0,-1,-2, ...) the series expansion formulas for the noninteger n* Slater-type orbitals (NiSTOs) in terms of integer n Slater-type orbitals(iSTOs) are derived. These formulas enable us to express the overlap integrals with NiSTOs through the overlap integrals over iSTOs with the same and different screening constants. By calculating concrete cases the convergence of the series for arbitrary values of noninteger principal quantum numbers and screening constants of NiSTOs and internuclear distances is tested. The accuracy of the results is quite high for quantum numbers, screening constants and location of STOs.

关键词：指数轨道游标量子数迭代积分 NiSTOS 原子核

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先进的奥钢联冷轧自动化方案

钢铁 2000年第10期35卷 43-47页

作者： M.Abikaram Y.leclercq R.Pichler 奥钢联工程技术公司

奥钢联可提供从可逆式轧机直到冷连轧联合机组的整套质量包 ,以高生产率和低成本生产优质冷轧带钢。重点介绍质量包的核心功能块 ,包括以成本函数和神经网络为基础的物理工艺模型 ,以及适用于所有操作条件、以闭环方式工作的先进的厚度... 详细信息

奥钢联可提供从可逆式轧机直到冷连轧联合机组的整套质量包 ,以高生产率和低成本生产优质冷轧带钢。重点介绍质量包的核心功能块 ,包括以成本函数和神经网络为基础的物理工艺模型 ,以及适用于所有操作条件、以闭环方式工作的先进的厚度、张力和平直度控制技术。

关键词：冷轧自动化质量包厚度张力平直度带钢

Simulation of detection and scattering of sound waves by the lateral line of a fish

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Chinese Physics B 2022年第2期31卷 398-404页

作者： V M Adamyan i Y Popov i V Blinova V V Zavalniuk Odessa i.i.Mechnikov National University Dvoryanskaya Str.2Odesa65082Ukraine iTMO University Kronverkskiy49Saint Petersburg197101Russia Odessa Military Academy 10 Fontanska RoadOdesa 65009Ukraine

A solvable model of lateral line of a fish based on a wave equation with additional boundary conditions on a set of isolated points is *** the framework of this model it is shown that the ratio of pressures on lateral lines on different fish flanks,as well as the cross section of sound scattering on both the lines,strongly depends on angles of incidence of incoming sound *** strong angular dependence of the pressure ratio seems to be sufficient for the fish to determine the directions from which the sound is coming.

关键词： acoustic equation point self-adjoint perturbations of Laplace operator scattering lateral line

Efficacy and Safety of Misoprostol Vaginal insert to induce Labor beyond 40 + 0 Weeks of Gestation

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Open Journal of Obstetrics and Gynecology 2021年第10期11卷 1333-1341页

作者： Catharina Krause Christian Rudlowski Melanie Erices-leclercq David Tenckhoff Sabine Lubig Department of Obstetrics and Gynecology Lutheran Hospital Begisch Gladbach Germany University Hospital Bonn Bonn Germany

Objective: Misoprostol vaginal insert (MVi) is proven to induce labor by a continuously release of PGE1. Previous reports showed that MVi reduced induction to delivery time as well as active labor time but it also inc... 详细信息

Objective: Misoprostol vaginal insert (MVI) is proven to induce labor by a continuously release of PGE1. Previous reports showed that MVI reduced induction to delivery time as well as active labor time but it also increased uterine tachysystole. Here we attempted to clarify whether MVI is safe and efficient for women with pregnancies >40 weeks in a single institute. Methods: This study was performed in Lutheran Hospital Bergisch Gladbach, Germany 2014-2019. A total of 304 women between 40 + 0 to 42 + 0 weeks underwent labor induction with MVI. Outcomes were: 1) maternal: time from insertion to delivery, interventions, mode of delivery, and uterine tachysystole, 2) neo-natal: cord blood pH, APGAR scores, and admission to a neonatal clinic. This study ended unexpectedly due to the withdrawal of MVI (MisodelTM) in September 2019. Results: 75.7% (n = 230) of women gave birth within 24 hours after MVI placement. 72.2% (n = 140) nulliparous women and 81.8% (n = 90) parous women delivered within 24 hours. In two cases emergency CS wasily:Verdana;"> required. 67.8% (n = 206) of women delivered vaginal. 2.3% (n = 7) of cord pH levels were be

关键词： Misoprostol Vaginal insert induction of Labor Caesarean Section Vaginal Delivery

Mini-loop ligation of a bleeding duodenal Dieulafoy's lesion

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World Journal of Gastroenterology 2013年第22期19卷 3505-3507页

作者： Marija Gomeri Pali Neven Ljubii Division of Gastro-enterology and Hepatology Department of Internal Medicine Medical and Dental Faculty "Sestre Milosrdnice" University Hospital Center University of Zagreb 10000 Zagreb Croatia

Two percent of gastrointestinal hemorrhages are caused by Dieulafoy's lesions, which are located in duodenum in only 15% of cases. There are no recommendations regarding the prime endoscopic treatment technique for this condition. A 61-year-old woman presented with melena without signs of hemodynamic instability. During an urgent upper endoscopy, blood oozing from the normal mucosa of the duodenum was seen and this was classified as a Dieulafoy's lesion. A mini-loop was opened at the rim of a transparent ligation chamber, at the end of the endoscope, and after aspiration of the lesion, closed and detached. Complete hemostasis was achieved without early or postponed complications. in every day clinical practice, mini-loop ligation is rarely used because of possible complications, such as site ulceration, organ perforation, re-bleeding and possible inexperience of the operator. To the best of our knowledge this is the first case of successful treatment of bleeding duodenal Dieulafoy's lesion by mini-loop ligation.

关键词： Dieulafoy’s lesion Duodenum Endoscopy Mini-loop Hemostasis