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A kinetic model for a single step biodiesel production from a high free fatty acid (FFA) biodiesel feedstock over a solid heteropolyacid catalyst

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Green Energy & Environment 2019年第3期4卷 328-341页

作者： Aashish Gaurav Stéphane Dumas Chau t.Q.Mai Flora t.t.ng Department of Chemical Engineering University of Waterloo

Production of biodiesel from yellow grease(waste cooking oil and waste animal fats) is fast emerging as a promising alternative to address the twin challenges before the biodiesel industry today-fluctuation in prices of vegetable oil and the food versus fuel debate. Yellow grease has a high percentage of free fatty acids(FFA) and proves to be an unsuitable feedstock for biodiesel production from commercially viable alkalicatalyzed production systems due to saponification problems.'Green' methodologies based on heterogeneous solid acid catalyzed reactions have the potential to simultaneously promote esterification and transesterification reactions of yellow grease to produce biodiesel without soap formation and offer easy catalyst separation without generation of toxic streams. this paper presents kinetic studies for the conversion of model yellow grease feeds to biodiesel using a heteropolyacid supported on alumina(HSiW/Al2O3) using a batch autoclave. three model yellow grease feeds were prepared using canola oil with added FFA such as palmitic, oleic and linoleic acid. A pseudo homogeneous kinetic model for the parallel esterification and transesterification was developed. the rate constants and activation parameters for esterification and transesterification reactions for the model yellow grease feeds were determined. the rate constants for esterification are higher than the transesterification rate constants. the kinetic model was validated using the experimental biodiesel data obtained from processing a commercial yellow grease feed. the kinetic model could be used to design novel processes to convert various low-value waste oils, fats and non-food grade oils to sustainable biodiesel.

关键词： Yellow grease Canola oil Free fatty acids Heteropolyacid Kinetics for esterification and transesterification

A new green process for biodiesel production from waste oils via catalytic distillation using a solid acid catalyst-Modeling, economic and environmental analysis

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Green Energy & Environment 2016年第1期1卷 62-74页

作者： Aashish Gaurav Flora t.t.ng Garry L.Rempel Department of Chemical Engineering University of Waterloo

the challenges in the chemical processing industry today are environmental concerns, energy and capital costs. Catalytic distillation(CD) is a green reactor technology which combines a catalytic reaction and separation via distillation in the same distillation column. Utilization of CD in chemical process development could result in capital and energy savings, and the reduction of greenhouse gases. the efficacy of CD and the economic merits, in terms of energy and equipment savings, brought by CD for the production of biodiesel from waste oil such as yellow grease is quantified. Process flow sheets for industrial routes for an annual production of 10 million gallon AStM purity biodiesel in a conventional process(reactor followed by distillation) and CD configurations are modeled in Aspen Plus. Material and energy flows, as well as sized unit operation blocks, are used to conduct an economic assessment of each process. total capital investment, total operat.ng and utility costs are calculated for each process. the waste oil feedstock is yellow grease containing both triglyceride and free fatty acid. Both transesterification and esterification reactions are considered in the process simulations. Results show a significant advantage of CD compared to a conventional biodiesel processes due to the reduction of distillation columns, waste streams and greenhouse gas emissions. the significant savings in capital and energy costs together with the reduction of greenhouse gases demonstrate that process intensification via CD is a feasible and new green process for the biodiesel production from waste oils.

关键词： Yellow grease Catalytic distillation Aspen plus economic analyzer Process intensification

青藏高原1981-2015年暖季降水变化趋势:受控于大尺度环流型变化

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北京大学学报（自然科学版） 2024年第1期60卷 133-144页

作者：孙亚伟吴振鹏黎立页张庆红北京大学物理学院大气与海洋科学系北京100871 92154部队烟台264000 中国气象科学研究院北京100081

利用最新的高时空分辨率融合降水数据集,研究青藏高原的长期降水变化趋势。结果表明,在1981—2015年的暖季(5—9月),青藏高原降水量显著增加(格点平均趋势为0.9 mm/a),其东北部、中部和西部最为显著。采用t模态倾斜旋转主成分分析法(PC... 详细信息

利用最新的高时空分辨率融合降水数据集,研究青藏高原的长期降水变化趋势。结果表明,在1981—2015年的暖季(5—9月),青藏高原降水量显著增加(格点平均趋势为0.9 mm/a),其东北部、中部和西部最为显著。采用t模态倾斜旋转主成分分析法(PCt),将青藏高原500 hPa位势高度场分为9个典型环流型,发现第2和第4环流型(t2和t4)是暖季降水量增加的主导环流型(Dt)。Dt位势高度场为西低东高的“槽脊对峙”分布,青藏高原暖季降水量增加体现在Dt主导降水日数和日均降水量的共同增加。除Dt环流型数量的增加导致青藏高原中西部降水增加外,降水增加机制还包括降水条件的优化,即t2以“槽脊对峙”加强为驱动的动力条件优化为主导,t4以“水汽滞增”加强为驱动的热力条件优化为主导。

关键词：青藏高原(tP) 降水长期趋势大尺度环流

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金融秩序维护与企业ESG表现——来自金融司法审判的证据

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经济学动态 2024年第7期 92-110页

作者：魏建王慧敏薛启航山东大学人文社科期刊社山东大学中泰证券金融研究院 250100 山东大学经济学院 250100

司法行为的社会影响备受关注,但对该问题的研究缺乏充足的经验证据。从金融秩序维护的角度,利用中国裁判文书网公布的破坏金融管理秩序刑事一审判决书构建地级市层面的金融司法审判指标,探讨金融司法审判对企业ESG表现的影响。研究结果... 详细信息

司法行为的社会影响备受关注,但对该问题的研究缺乏充足的经验证据。从金融秩序维护的角度,利用中国裁判文书网公布的破坏金融管理秩序刑事一审判决书构建地级市层面的金融司法审判指标,探讨金融司法审判对企业ESG表现的影响。研究结果显示:企业所在地的金融司法审判效率越高、上诉率越低,企业的ESG表现越好。机制分析表明,金融司法审判主要通过降低信息不对称程度、缓解企业融资约束以及增强企业风险管理意识来提高企业的ESG表现水平。进一步分析发现,对于那些拥有较多法律背景高管的企业以及处于银行机构密集城市的企业,金融司法审判的影响更加显著;而且,金融司法审判的改善还有助于降低ESG不确定性程度,以及强化ESG对企业价值的提升效应。因此,应当持续加强金融司法审判的专业化和严格化,鼓励企业主动承担ESG责任,从而实现企业和社会的“双赢”局面。

关键词：金融秩序维护审判效率上诉率 ESG

Nonlinear optics on silicon-rich nitride--a high nonlinear figure of merit CMOS platform[Invited]

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Photonics Research 2018年第5期6卷 I0075-I0091页

作者： D.t.H.tAN K.J.A.OoI D.K.t.ng Photonics Devices and Systems Group Singapore University of Technology and Design8 Somapah Rd.Singapore 487372Singapore Data Storage Institute Agency for ScienceTechnology and Research(A*STAR)2 Fusionopolis Way#08-01 InnovisSingapore 138634Singapore

CMOS platforms with a high nonlinear figure of merit are highly sought after for high photonic quantum efficiencies, enabling functionalities not possible from purely linear effects and ease of integration with CMOS electronics. Silicon-based platforms have been prolific amongst the suite of advanced nonlinear optical signal processes demonstrated to date. these include crystalline silicon, amorphous silicon, Hydex glass, and stoichio- metric silicon nitride. Residing between stoichiometric silicon nitride and amorphous silicon in composition, silicon-rich nitride films of various formulations have emerged recently as promising nonlinear platforms for high nonlinear figure of merit nonlinear optics. Silicon-rich nitride films are compositionally engineered to create bandgaps that are sufficiently large to eliminate two-photon absorption at telecommunications wavelengths while enabling much larger nonlinear waveguide parameters （5x-500x） than those in stoichiometric silicon uitride. this paper reviews recent developments in the field of nonlinear optics using silicon-rich nitride platforms, as well as the outlook and future opportunities in this burgeoning field.

关键词： Nonlinear optics silicon-rich nitride a high Nonlinear figure of merit CMOS platform

中药足浴加穴位贴敷配合认知领悟疗法对重症脓毒血症连续性血液净化患者心理状态、生命质量的影响

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中国现代药物应用 2024年第17期18卷 1-6页

作者：周雯遂川县人民医院肾内科 343900

目的探讨重症脓毒血症连续性血液净化干预中中药足浴加穴位贴敷配合认知领悟疗法对患者心理状态、生命质量的影响。方法回顾性选取重症脓毒血症连续性血液净化患者68例,依据干预方法不同分为配合干预组、传统干预组,各34例。传统干预... 详细信息

目的探讨重症脓毒血症连续性血液净化干预中中药足浴加穴位贴敷配合认知领悟疗法对患者心理状态、生命质量的影响。方法回顾性选取重症脓毒血症连续性血液净化患者68例,依据干预方法不同分为配合干预组、传统干预组,各34例。传统干预组患者采用传统干预方法,配合干预组患者采用中药足浴加穴位贴敷配合认知领悟疗法。比较两组肾功能、实验室指标、血流动力学、病情严重程度、心理状态、生命质量,临床疗效,并发症发生情况,不良事件发生情况,干预质量评分及住院时间,干预满意度。结果干预后,两组患者的血肌酐(Scr)、尿素氮(BUN)、肿瘤坏死因子-α(tNF-α)、急性生理与慢性健康评分系统Ⅱ(APACHEⅡ)评分、焦虑评分、抑郁评分均低于干预前,白细胞介素(IL)-1、IL-10、辅助性t淋巴细胞1/辅助性t淋巴细胞2(th1/th2)、血栓长度、血浆粘度、全血高切粘度、血小板粘附率、生命质量评分均高于干预前(PtNF-α(303.10±47.70)ng/L、血栓长度(54.02±9.56)mm、血浆粘度(2.02±0.30)mPa·s、全血高切粘度(6.23±0.38)mPa·s、血小板粘附率(82.02±9.03)%、APACHEⅡ评分(12.92±1.83)分、焦虑评分(23.55±3.83)分、抑郁评分(24.54±3.85)分均低于传统干预组的(152.41±16.82)mmol/L、(7.27±0.82)mmol/L、(458.30±77.40)ng/L、(59.12±9.02)mm、(2.36±0.33)mPa·s、(6.75±0.36)mPa·s、(90.75±9.04)%、(15.07±1.96)分、(38.66±3.71)分、(38.61±3.91)分,IL-1(35.70±0.34)ng/L、IL-10(242.70±17.30)ng/L、th1/th2(15.12±0.47)、生命质量评分(83.66±5.11)分高于传统干预组的(31.61±0.45)ng/L、(184.10±23.90)ng/L、(10.22±0.03)、(75.80±4.94)分(P<0.05)。配合干预组患者的总有效率94.12%(32/34)高于传统干预组的73.53%(25/34)(χ^(2)=5.314,P<0.05)。配合干预组患者的并发症发生率11.76%(4/34)低于传统干预组的32.35%(11/34)(χ^(2)=4.191,P<0.05)。配合干预组患者的不良事件发生率11.76%(4/34)低于传统干预组的41.18%(14/34)(χ^(2)=7.556,P<0.05)。配合干预组患者的操作技术、干预管理评分分别为(98.72±1.14)、(95.70±1.74)分,均高于传统干预组的(80.91±1.00)、(82.62±1.95)分,住院时间(8.91±1.34)d短于传统干预组的(12.27±2.30)d(P<0.05)。配合干预组患者的干预满意度91.18%(31/34)高于传统干预组的70.59%(24/34)(χ^(2)=4.660,P<0.05)。结论重症脓毒血症连续性血液净化干预中采用中药足浴加穴位贴敷配合认知领悟疗法较传统干预更能对患者心理状态、生命质量进行改善,是一项值得推广的护理措施。

关键词：重症脓毒血症连续性血液净化中药足浴穴位贴敷认知领悟疗法心理状态生命质量

Effect of a nitric oxide synthase inhibitor ng-nitro-L-arginine methyl ester on invasion of human colorectal cancer cell line SL-174t

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World Journal of Gastroenterology 2005年第40期11卷 6385-6388页

作者： Li-Bo YU Xin-Shu Dong wen-Zhou sun Dong-Lu Zhao Yue Yang Department of GeneralSurgery the Affiliated Tumor Hospital of Harbin MedicalUniversity Harbin 150040 Heilongiiang Province China Cancer Research Institute of HarbinMedical University Harbin 150040 Heilongjiang Province China

AIML to investigate the effect and mechanism of action of the nitric oxide synthase （NOS） inhibitor ng-nitro-L-arginine methyl ester （L-NAME） on invasion and metastasis of human colorectal cancer cell line SL-174t. MEtHODS： Human colorectal cancer cel4 line SL-174t was cultured and treated separately with four different dosages of L-NAME for 72 h, Nitric oxide （NO） production was measured with Griess reagent, the effect of L-NAME on invasion and migration of SL-174t cells were evaluated by using transwell chambers attached with polycarbonate filters and reconstituted basement membrane （Matrigel）, Rt-PCR was performed to determine the mRNA levels of matrix metalloproteinase-2 （MMP-2） and tissue inhibitor metalloproteinase-2 （tIMP-2）,RESULtS： L-NAME could significantly inhibit NO production of SL-174t in a dose-dependent manner. After being treated for 72 h with 0.2, 0.4, 0.8, and 1.0 mmol/L L- NAME, respectively, the ability of the L-NAME treated SL- 174t cells to invade the reconstituted basement membrane decreased significantly （t = 8.056, P〈0.05; t= 14.467, P〈0.01; t= 27.785, P〈0.01; and t= 29.405, P〈0.01, respectively） and the inhibition rates were 10.29%, 19.62%, 34.08%, and 42.23%, respectively. Moreover, L-NAME could inhibit migration of SL-174t cells, and the inhibition rates were 20.76%, 24.95%, 39.43%, and 46. 85% for L-NAME at 0.2, 0.4, 0.8, and 1.0 mmol/L, respectively （t = 15.116, P〈0.01）. In addition, after treatment with L-NAME, expression of MMP-2 mRNA was significantly decreased （t = 71.238, P〈0.01） and that of tIMP-2 mRNA was markedly increased （t = -13.020, P〈0.01）. CONCLUSION： L-NAME exerts anti-invasive and anti- metastatic effects on SL-174t cell line via downregulat.ng MNP-2 mRNA expression and upregulat.ng tIMP-2 mRNA expression.

关键词： Colorectal Neoplasms Neoplasm Invasiveness Cell Line, tumor Cell Movement Dose-Response Relationship, Drug Female Gelatinase A Humans Male ng-Nitroarginine Methyl Ester Nitric Oxide Nitric Oxide Synthase inhibitors tissue Inhibitor of Metalloproteinase-2

Is hydrotherapy an appropriate form of exercise for elderly patients with biventricular systolic heart failure?

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Journal of Geriatric Cardiology 2012年第4期9卷 408-410页

作者： Bente Grüer Sve 1v Margareta Scharin t.ng sa Cider the Wallenberg Laboratory Department of Molecular and Clinical Medicine Institute of Medicine at Sahlgrenska Academy University of Gothenburg Bruna Str ket 16 SE-413 45 Gothenburg Sweden Physiotherapy and Occupational Department Institute of Neuroscience and Physiology/Physiotherapy at Sahlgrenska Academy University of Gothenburg Vita straket 13 SE-413 45 Gothenburg Sweden

Hydrotherapy (exercise in warm water) is considered to be a safe and beneficial method to use in the rehabilitation of stable heart failure patients, but there is little information on the effect of the increased venous return and enhanced preload in elderly patientswith biventricular heart failure. We present a case of an elderly man whowas recruited to participate in a hydrotherapy study. We compared echocardiographic data duringwarm water immersion with land measurements, and observed increases in stroke volume from 32 mL (land) to 42 mL (water), left ventricular ejection fraction from 22% to 24%, left ventricular systolic velocity from 4.8 cm/s to 5.0 cm/s and left atrioventricular plane displacement from 2.1 mm to 2.2 mm. By contrast, right ventricular systolic velocity decreased from 11.2 cm/s to 8.4 cm/s and right atrioventricular plane displacement from 8.1 mm to 4.7 mm. the tricuspid pressure gradient rose from 18 mmHg on land to 50mmHg during warm water immersion. thus, although left ventricular systolic function was relatively unaffected during warm water immersion, we observed a decrease in right ventricular function with an augmented right ventricular pressure. We recommend further investigations to observe the cardiac effect of warm water immersion on patients with biventricular systolic heart failure and at risk of elevated right ventricular pressure.

关键词： Echocardiography Heart failure Hydrotherapy Pulmonary hypertension

OFDM-WDM LR-PON with ultra-bendable fiber for last-mile distribution of quintuple-play service

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Chinese Optics Letters 2013年第8期11卷 18-23页

作者： tiago M. F. Alves Rakesh Sambaraju Adolfo V. t. Cartaxo Anthony ng'oma Instituto de telecomunicao es Department of Electrical and Computer Engineering Instituto Superior Tcnico Technical University of Lisbon1049-001 Lisbon Portugal Science and technology Department Corning Incorporated One Riverfront PlazaCorning NY 14831 USA

the provision of quintuple-play services along wavelength division multiplexed （WDM） long-reach passive optical networks （LR-PONs） employing an ultra-bendable fiber in last-mile distribution is demonstrated experimentally. Particularly, the simultaneous transmission of three 100-GHz-spaced optical channels for the provision of double sideband orthogonal frequency-division multiplexing （OFDM） wireless and wired quintuple-play services to the premises of users located at 75, 85, and 100 km away from the central office is demonstrated. the OFDM-WDM LR-PON is tested considering the last-mile fiber distribution suffering from severe bending conditions without optical dispersion compensation. the experiments are performed for a worst last-mile fiber bending case emulated by considering a Corning ClearCurve fiber experiencing 20 bends and a bend radius of 7.5 mm. All the OFDM signals received at the premises of users present error vector magnitude （EVM） levels compliant with the EVM thresholds of the corresponding standards. An EVM degradation in the OFDM signals received by each user not exceeding 0.8 dB due to the last-mile distribution fiber is achieved.

关键词： WDM PON OFDM-WDM LR-PON with ultra-bendable fiber for last-mile distribution of quintuple-play service LR

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