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Predicting the elemental compositions of solid waste using ATR-FTIR and machine learning

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Frontiers of Environmental Science & Engineering 2023年第10期17卷 41-54页

作者： haoyang Xian Pinjing he Dongying lan Yaping Qi Ruiheng Wang Fan lü hua Zhang jisheng long Institute of Waste Treatment&Reclamation College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China Shanghai Engineering Research Center of Multi-source Solid Wastes Co-processing and Energy Utilization Shanghai 200092China Shanghai SUS Environment Co. Ltd.Shanghai 201703China

Elemental composition is a key parameter in solid waste treatment and disposal. This study has proposed a method based on infrared spectroscopy and machine learning algorithms that can rapidly predict the elemental composition (C, h, n, S) of solid waste. Both noise and moisture spectral interference that may occur in practical application are investigated. By comparing two feature selection methods and five machine learning algorithms, the most suitable models are selected. Moreover, the impacts of noise and moisture on the models are discussed, with paper, plastic, textiles, wood, and leather as examples of recyclable waste components. The results show that the combination of the feature selection and K-nearest neighbor (Knn) approaches exhibits the best prediction performance and generalization ability. Particularly, the coefficient of determination (R2) of the validation set, cross validation and test set are higher than 0.93, 0.89, and 0.97 for predicting the C, h, and n contents, respectively. Further, Knn is less sensitive to noise. Under moisture interference, the combination of feature selection and support vector regression or partial least-squares regression shows satisfactory results. Therefore, the elemental compositions of solid waste are quickly and accurately predicted under noise and moisture disturbances using infrared spectroscopy and machine learning algorithms.

关键词： Elemental composition Infrared spectroscopy Machine learning Moisture interference Solid waste Spectral noise

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过渡金属共价化合物MlIXxZz分类法

化学通报 1987年第6期 18-20页

作者： M.l.h.Green 英国牛津大学教授

金属有机化合物的MlIXxZz分类法直观地反映了化合物的电子结构和配位环境。同时,在一定程度上反映了化合物的结构与其稳定性、反应活性的关系。这一方法在金属有机化学的教学和研究中也具有一定意义。

关键词：过渡金属电子结构过渡元素中心原子 MlIXxZz 过渡金属化合物分类法情报检索共价化合物配位环境配位体

低雾化低挥发性汽车用新型聚氨酯泡沫塑料助剂

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聚氨酯工业 2003年第3期18卷 43-46页

作者： Muller l Ghobary h E Derderian E j Robinson K K Chong S M Crompton Europe Crompton EuropeCrompton Corporation USACrompton Corporation USACrompton Specialties Asia Pacific

康普顿公司开发了一系列适用于消除或减少汽车内饰件中胺扩散或雾化的添加剂 ,其中包括快速、有效的生产用零扩散催化剂和低雾化表面活性剂。该系列添加剂能大大降低泡沫制品中的胺扩散 ,与异氰酸酯和多元醇原料能组成最佳组合 ,以保持... 详细信息

康普顿公司开发了一系列适用于消除或减少汽车内饰件中胺扩散或雾化的添加剂 ,其中包括快速、有效的生产用零扩散催化剂和低雾化表面活性剂。该系列添加剂能大大降低泡沫制品中的胺扩散 ,与异氰酸酯和多元醇原料能组成最佳组合 ,以保持良好的泡沫物理性能。

关键词：低雾化低挥发性塑料助剂汽车材料聚氨酯泡沫塑料异氰酸酯多元醇

关于大麻素-1受体阻断剂利莫那班对超重或肥胖患者体重和心脏代谢危险因素影响的随机对照试验:RIO-北美研究

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世界核心医学期刊文摘（心脏病学分册） 2006年第6期2卷 6-7页

作者： Pi-Sunyer F.X. Aronne l.j. heshmati h.M. 任付先 Obesity Research Center St. Luke's- Roosevelt Hospital WH1020 1111 Amsterdam Ave New York NY 10025 United States Dr.

Context: Rimonabant, a selective cannabinoid- 1 receptor blocker, may reduce body weight and improve cardiometabolic risk factors in patients who are overweight or obese. Objective: To compare the efficacy and safety of rimonabant with placebo each in conjunction with diet and exercise for sustained changes in weight and cardiometabolic risk factors over 2 years. Design, Setting, and Participants: Randomized, double- blind, placebo- controlled trial of 3045 obese(body mass index ≥ 30) or overweight(body mass index >27 and treated or untreated hypertension or dyslipidemia) adult patients at 64 US and 8 Canadian clinical research centers from August 2001 to April 2004. Intervention: After a 4- week single- blind placebo plus diet(600 kcal/d deficit) run- in period, patients were randomized to receive placebo, 5 mg/d of rimonabant, or 20 mg/d of rimonabant for 1 year. Rimonabant- treated patients were rerandomized to receive placebo or continued to receive the same rimonabant dose while the placebo group continued to receive placebo during year 2. Main Outcome Measures: Body weight change over year 1 and prevention of weight regain during year 2. Additional efficacy measures included changes in waist circumference, plasma lipid levels, and other cardiometabolic risk factors. Results: At year 1, the completion rate was 309(51% ) patients in the placebo group, 620(51% ) patients in the 5 mg of rimonabant group, and 673(55% ) patients in the 20 mg of rimonabant group. Compared with the placebo group, the 20 mg of rimonabant group produced greater mean(SEM) reductions in weight(- 6.3 [0.2] kg vs - 1.6[0.2] kg; Pnce(- 6.1 [0.2] cm vs- 2.5[0.3] cm; Pnd level of triglycerides(percentage change,- 5.3[1.2] vs 7.9 [2.0]; Pnd a greater increase in level of high- density lipoprotein cholesterol(percentage change, 12.6 [0.5] vs 5.4 [0.7]; Pnts who were switched from the 20 mg of rimonabant group to the placebo group during y

关键词：随机对照试验肥胖患者受体阻断剂危险因素心脏代谢大麻素体重超重北美限制饮食

Studies of a possible new herbig Ae/Be star in the open cluster nGC 7380

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Research in Astronomy and Astrophysics 2012年第2期12卷 167-176页

作者： Blesson Mathew D.P.K.Banerjee n.M.Ashok Annapurni Subramaniam Bhaskaran Bhavya Vishal joshi Astronomy and Astrophysics Division Physical Research LaboratoryNavrangapura Indian Institute of Astrophysics Cochin University of Science and Technology

We present a study of the star 2MASS j22472238＋5801214 with the aim of identifying its true nature which has hitherto been uncertain. This object, which is a member of the young cluster nGC 7380, has been variously proposed to be a Be star, a D-type symbiotic and a herbig Ae/Be star in separate studies. here we present optical spectroscopy, near-IR photometry and narrow band hα imaging of the nebulosity in its environment. Analysis of all these results, including the spectral energy distribution constructed from available data, strongly indicate the source to be a herbig Ae/Be star. The star is found to be accompanied by a nebulosity with an interesting structure. A bow-shock shaped structure, similar to a cometary nebula, is seen very close to the star with its apex oriented towards the photoionizing source of this region （i.e. the star Dh Cep）. An interesting spectroscopic finding, from the forbidden [StI] 6716, 6731A and [OI] 6300A lines, is the detection of a blue-shifted high velocity outflow （200 -t-50 km s-1） from the star.

关键词： stars: emission-line - Be - stars: pre-main sequence -- stars: winds outflows -- galaxies: star clusters: individual: nGC 7380

Boosting oxygen reduction activity and CO_(2) resistance on bismuth ferrite-based perovskite cathode for low-temperature solid oxide fuel cells below 600℃

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journal of Energy Chemistry 2024年第3期90卷 600-609,I0013页

作者： juntao Gao Zhiyun Wei Mengke Yuan Zhe Wang Zhe lü Qiang li lingling Xu Bo Wei School of Physics Harbin Institute of TechnologyHarbin 150001HeilongjiangChina Key laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080HeilongjiangChina School of Physics and Electronic Engineering Harbin Normal UniversityHarbin 150025HeilongjiangChina

Developing efficient and stable cathodes for low-temperature solid oxide fuel cells(lT-SOFCs) is of great importance for the practical ***,we propose a series of Sm-modified Bi_(0.7-x)Sm_xSr_(0.3)FeO_(3-δ) perovskites as highly-active catalysts for *** doping can significantly enhance the electrocata lytic activity and chemical stability of *** 600℃,Bi_(0.675)Sm_(0.025)Sr_(0.3)FeO_(3-δ)(BSSF25) cathode has been found to be the optimum composition with a polarization resistance of 0.098 Ω cm^2,which is only around 22.8% of Bi_(0.7)Sr_(0.3)FeO_(3-δ)(BSF).A full cell utilizing BSSF25 displays an exceptional output density of 790 mW cm^(-2),which can operate continuously over100 h without obvious *** remarkable electrochemical performance observed can be attributed to the improved O_(2) transport kinetics,superior surface oxygen adsorption capacity,as well as O_(2)p band centers in close proximity to the Fermi ***,larger average bonding energy(ABE) and the presence of highly acidic Bi,Sm,and Fe ions restrict the adsorption of CO_(2) on the cathode surface,resulting in excellent CO_(2) *** work provides valuable guidance for systematic design of efficient and durable catalysts for lT-SOFCs.

关键词： low-temperature solid oxide fuel cell Perovskite cathode DFT calculations CO_(2) tolerance

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赤道地区海水的垂直混合

海洋预报 1988年第S1期 1-15页

作者： h.peters,M.C.Gregg,D.R.Caldwell,j.n.Moum,杨启升华盛顿大学应用物理试验室华盛顿大学应用物理试验室俄勒冈州立大学海洋学院俄勒冈州立大学海洋学院西雅图西雅图科瓦利斯科瓦利斯

虽然自1972年就开始了赤道湍流的测量,但是,直到1984年在赤道太平洋水域及其附近所进行的广泛而系统的测量才使我们对湍流混合及其时间变化有了崭新的认识。湍流活动正如我们所预料的那样,是如此巨大;但是它随时间的变化,却远远超过预... 详细信息

虽然自1972年就开始了赤道湍流的测量,但是,直到1984年在赤道太平洋水域及其附近所进行的广泛而系统的测量才使我们对湍流混合及其时间变化有了崭新的认识。湍流活动正如我们所预料的那样,是如此巨大;但是它随时间的变化,却远远超过预料之外,日变化尤其如此,夜间平均湍流动能耗散率是白天的一百倍。这种变化发生在温跃层以及混合层中。与之有关的一些问题是:(1)在什么纬度和经度上,以及在什么季节会出现这种周期日变化?(2)是什么引起了这种较长期的时间变化?是大气强迫作用还是通过赤道波的切变场调制?(3)内波起什么样的作用?(4)能否用理查逊数来使湍流作用参数化?如果可以的话,那么合适的尺度有多大?现在已经取得了参数化,有关这些问题的观测结果,并不能肯定地解决这些问题。现在就取得的一些证据展开讨论。

关键词：平均切变耗散率理查逊数湍流混合赤道湍流耗散汤姆森参数化赤道地区海水

Petrogenesis of the crater-facies Tokapal kimberlite pipe,Indrvati Basin,Central India

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Geoscience Frontiers 2014年第6期5卷 781-790页

作者： n.V.Chalapathi Rao B.lehmann B.K.Panwar Alok Kumar D.Mainkar Department of Geology Centre of Advanced StudyBanaras Hindu UniversityVaranasi 221005India Mineral Resources Technical University of Clausthal38678 Clausthal-ZellerfeldGermany Directorate of Geology and Mining RaipurChhattisgarh 492007India

new geochemical data of the crater-facies Tokapal kimberlite system sandwiched between the lower and upper stratigraphic horizons of the Mesoproterozoic lndravati Basin a：：e presented. The kimberlite has been subjected to extensive and pervasive low-temperature alteration. Spinel is the only primary phase identifiable, while olivine macrocrysts and juvenile lapilli are largely pseudomorphed （talc-serpentine- carbonate alteration）. however, with the exception of the alkalies, major element oxides display systematic fractionation trends; likewise, hFSE patterns are well correlated and allow petrogenetic interpretation. Various crustal contamination indices such as （SiO2 ＋ AI：：O3 ~ na20）]（MgO ~ K20） and Si] Mg are close to those of uncontaminated kimberlites. Similar la]Yb （＇79-109） of the Tokapal samples with those from the kimberlites of Wajrakarur （73-145） and narayanpet （72-156）, Eastern Dharwar craton, southern India implies a similarity in their genesis. In the discriminant plots involving hFSE the Tokapal samples display strong affinities to Group 1I kimberlites from southern Africa and central India as well as to ＇transitional kimberlites＇ from the Eastern Dharwar craton, southern India, and those from the Prieska and Kuruman provinces of southern Africa. There is a striking ~;imilarity in the depleted-mantle （TOM） nd model ages of the Tokapal kimberlite system, Bastar craton, th~ kimberlites from nKF and WKE Eastern Dharwar craton, and the Majhgawan diatreme, Bundelkhand craton, with the emplacement age of some of the lamproites from within and around the Palaeo^Mesoproterozoic Cuddapah basin, southern India. These similar ages imply a major tectonomagmatic event, possibly related to the break- up of the supercontinent of Columbia, at 1.3-1.5 Ga across the l：hree cratons. The ＇transitional＇ geochemical features displayed by many of the Mesoproterozoic po~：assic-ultrapotassic rocks, across these Indian cratons are inferred to be memories of the metasomatising f

关键词： Kimberlite Tokapal Columbia Bastar craton India

Concentrated Standing Tailwater： A Mechanism for nutrient Delivery to Downstream Aquatic Ecosystems

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journal of Agricultural Science and Technology(B) 2011年第5期1卷 773-777页

作者： R. Krogert M. T. Moore j. l. Farris Department of Wildlife Fisheries and Aquaculture P.O. Box 9690 Mississippi State MS 39762 USA USDA-Agricultural Research Service national Sedimentation laboratory Water Quality and Ecology Research Unit P.O. Box1157 Oxford ~14S 38655 USA Arkansas Biosciences Institute Arkansas State University P.O. Box 639 Jonesboro AR 72467 USA

Contribution of first flush runoff events from intense rainfall to downstream aquatic ecosystems are often reported in terms of sediment and nutrient delivery, with hardly any consideration to the contribution that standing, concentrated tailwater in primary aquatic systems makes to downstream nutrient loads. Two geographically distinct studies （jonesboro Arkansas, and Stoneville Mississippi; 4 studies, n = 30） evaluated the effectiveness of drainage ditch systems to mitigate nutrient concentrations and loads. Within each independent study all experimental ditches had elevated background nutrient concentrations as a result of standing water, prior to the start of each simulated runoff experiment. These concentrations remained elevated 15-30 minutes post the start of each simulation as the concentrated, impounded water was pushed out through each system. In both these systems, it was hypothesized that water had accumulated in the respective drainage ditches and had been concentrated though evaporation and aquatic macrophyte transpiration. It is theorized that additional controlled drainage with improved dilution and hydraulic residence management.

关键词： nutrient ditches wetlands could decrease the potential of concentration toxicity downstream