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用氯化铁、硫脲和盐水浸出法从复合硫化矿中回收金、银和铅

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黄金科学技术 1988年第4期 24-26页

作者： r.g.sandberg J.L.Huiatt 俸世兴

最近,美国矿山局研究了一种从复合铅-锌硫化矿中回收金、银和付产铅的水冶工艺.在40℃,用氯化铁（FeCl3）预浸6小时的条件下,可提取50%的锌,并生成不溶化的氯化银和氯化铅,然后在酸性硫脲中,温度为40℃的条件下浸出1～3小时,可提取出约... 详细信息

最近,美国矿山局研究了一种从复合铅-锌硫化矿中回收金、银和付产铅的水冶工艺.在40℃,用氯化铁（FeCl3）预浸6小时的条件下,可提取50%的锌,并生成不溶化的氯化银和氯化铅,然后在酸性硫脲中,温度为40℃的条件下浸出1～3小时,可提取出约85%的金和银。剩余的浸渣用 NaCl 溶液,在55℃的条件下,浸一小时可将氯化铅溶解,然后,在电解槽中,采用阳离子选择性渗透膜从该盐水溶液中回收铅,条件为:电流效率95%,电流密度100安/米2。使用过的 FeCl3浸出液在电流效率75—95%的条件下,可在阳极间隔氧化再生。

关键词：氯化铁氯化铅氯化银回收率氯化物实收率选择性渗透阳离子交换树脂硫化矿浸出液回收金浸出时间铅回收盐水

关于阿拉斯加难选金矿石的处理地区性金矿床经济发展的现代资料

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世界地质 1992年第4期11卷 118-124页

作者： W.r.Mcdondald J.L.Johnson r.g.sandberg 杨玉波

美国矿山局调查研究了金和银难选矿石的处理和精选,由于矿物复杂,它们难适应于常规的氰化技术。已调查了三种难选金的类型:金被包裹的砂矿;金被包裹在硫化物中;金被矿石中矿物从含金氰化溶液中掠夺。矿石处理包括:磨矿、浮选、氰化、空... 详细信息

美国矿山局调查研究了金和银难选矿石的处理和精选,由于矿物复杂,它们难适应于常规的氰化技术。已调查了三种难选金的类型:金被包裹的砂矿;金被包裹在硫化物中;金被矿石中矿物从含金氰化溶液中掠夺。矿石处理包括:磨矿、浮选、氰化、空气氧化、加压氧化、次氯酸盐氧化、焙烧和在浸出中加碳等。

关键词：金矿床矿石难选选矿浮游选矿

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Color and gloss Changes of a Lignin-Based Polyurethane Coating under Accelerated Weathering

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Journal of renewable Materials 2024年第2期12卷 305-323页

作者： Fatemeh Hassani Khorshidi Saeed Kazemi Najafi Farhood Najafi Antonio Pizzi Dick sandberg rabi Behrooz Department of Wood Science and Technology Faculty of Natural ResourcesTarbiat Modares UniversityTehranIran Department of resin and Additives Institute for Color Science and TechnologyP.O.Box 16765-654TehranIran LErMAB University of LorraineBlvd des AiguillettesNancy54000France Wood Science and Engineering LuleåUniversity of TechnologySkellefteåSweden

The purpose of this research study was to investigate the properties of polyurethane coatings based on lignin *** this purpose,the prepared coatings were applied to pine wood surfaces and weathered ***,color and gloss of the coatings were measured before and after the weathering *** emission scanning electron microscopy(FE-SEM)micrographs prepared from the coatings showed that the average size of nano-particles in the polyurethane substrate was approximately 500 *** magnetic resonance(13C-NMr)spectroscopy showed that strong urethane bonds were formed in the nano-lignin-based *** calorimetric analysis(DSC)test revealed that the glass-transition temperature(Tg)of lignin nanoparticles modified with diethylenetriamine(DETA)was 112.8℃ and Tg of lignin nano-particles modified with ethylenediamine(EDA)was 102.5℃,which is lower than the Tg of un-modified lignin(114.6℃)and lignin modified with DETA(126.8℃)and lignin modified with EDA(131.3℃).The coatings modified with lignin nano-particles had a greater change in *** lignin nano-particles in the modified coating are trapping hydroxyl radicals which reduces photoactivity and yellowing of the polyurethane by about 3 times compared to unmodified polyurethane *** weathering test,the nano-lignin-based coating had a rougher surface with a lower contact angle(0.78°)compared to the unmodified polyurethane coating(0.85°).

关键词： Amination propylene carbonate lignin biopolymer polyurethane coating polyol UN SDg 13

Finite-time consensus protocols for multi-dimensional multi-agent systems

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Control Theory and Technology 2020年第4期18卷 419-430页

作者： Jieqiang Wei Bart Besselink Junfeng Wu Henrik sandberg Karl H.Johansson Ericsson global AI Accelerator Torshamnsgatan 21StockholmSweden Bernoulli Institute for Mathematics Computer Science and Artificial IntelligenceUniversity of GroningenP.O.Box 4079700 GroningenAKThe Netherlands College of Control Science and Engineering Zhejiang University310027 HangzhouChina Division of Decision and Control Systems KTH Royal Institute of Technology10044 StockholmSweden

A fnite.-time consensus protocol is proposed for multi -dimensional multi- agent systems, using direction peserving signumcontrols. Flipp solutions and nonsmooh analysis tehniques are adopted to handle discontinuities. Suficient and ncessaryconditions are provided to guarantee infinte time convergence and boundedness of the solutions. It turns out that the numberof agents which have cotinuous contol law plays an ssenan role in fnite-tine conerence In adidio it is shown thatthe unit bals itoduced bylp, norms. where p ∈[1,∞] , are inariat for the closed lop.

关键词： Multi-agent systems Network consensus Finite time convergence Nonsmooth analysis

Laser-induced graphitization of a forest-based ink for use in flexible and printed electronics

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npj Flexible Electronics 2020年第1期4卷 149-158页

作者： Jesper Edberg robert Brooke Omid Hosseinaei Andreas Fall Kosala Wijeratne Mats sandberg rISE Bio-and Organic Electronics Bredgatan 3360221NorrköpingSweden rISE Bioeconomy Drottning Kristinas väg 6111428StockholmSweden

Laser-induced graphitization(LIg)is a method of converting a carbon-rich precursor into a highly conductive graphite-like carbon by laser *** method has shown great promise as a versatile and low-cost patterning *** we show for the first time how an ink based on cellulose and lignin can be patterned using screen printing followed by laser *** printing is one of the most commonly used manufacturing techniques of printed electronics,making this approach compatible with existing processing of various *** use of forest-based materials opens the possibility of producing green and sustainable ***-patterning of the ink enables carbon patterns without residual precursor between the *** investigated the effect of the ink composition,laser parameters,and additives on the conductivity and structure of the resulting carbon and could achieve low sheet resistance of 3.8Ωsq^(−1) and a high degree of *** demonstrated that the process is compatible with printed electronics and finally manufactured a humidity sensor which uses lignin as the sensing layer and graphitized lignin as the electrodes.

关键词： forest printing electronics

robot-assisted laparoscopic radical cystectomy with complete intracorporeal urinary diversion

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Asian Journal of Urology 2016年第3期3卷 156-166页

作者： Jason M.sandberg Ashok K.Hemal Department of Urology Wake Forest University School of MedicineWinstoneSalemNCUSA

robot-assisted radical cystectomy with intracorporeal urinary diversion(rArCICUD)has only recently been explored as a viable surgical option for patients with muscle-invasive bladder cancer seeking satisfactory oncologic control while benefiting from minimally invasive surgical *** by earlier open and laparoscopic work,initial descriptions of rArC-ICUD were published in 2003,and have since been followed by multiple larger case series which have suggested promising outcomes for our ***,the rate of adoption has remained relatively slow when compared to other robotassisted procedures such as the radical prostatectomy,likely owing to longer operative times,operative complexity,costs,and uncertainty regarding oncologic *** operative technique for rArC-ICUD has evolved over the past decade and several high-volume centers have shared tips to improve efficiency and make the operation possible for a growing number of *** there are still questions regarding economic costs,effectiveness,and generalizability of outcomes reported in published data,a growing dataset has brought us ever closer to the ***,we present our current operative technique for rArC-ICUD and discuss the state of the literature so that the urologist may hold an informed discussion with his or her patients.

关键词： Cystectomy robotics Urinary bladder neoplasms Urinary diversion

Influence of an intravenous infusion of amino acids and glucose on the pancreatic exocrine in rats

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Chinese Medical Journal 2004年第11期117卷 1659-1664页

作者：范博广 ke Andrén-sandberg Center for gastrointestinal Disease Taizhou Hospital Wenzhou Medical College Taizhou 318000 China Sahlgrenska University Hospital Gteborg Sweden

Background A number of reports based on both animal experiments and clinical investigations have pointed out that total parenteral nutrition (TPN) suppresses the function of the exocrine pancreas. Even though pancreatic hypotrophy and dysfunction resulting from TPN may be explained by several mechanisms, the clinically most important cause is that nutrients in circulation affect pancreatic secretion. The effect of nutrients on the exocrine pancreas is still controversial. The aim of the present study was, therefore, to clarify the influence of intravenous amino acids and hypertonic glucose in TPN solution on the exocrine pancreas. Methods Three mixed TPN solutions, consisting of 30% or 50% glucose or of 14% amino acids, were employed. Twenty-four male Sprague-Dawley rats were randomly divided into four groups, six rats in each group, including a control group and one group receiving each of the three TPN solutions. All animals were killed after 10 days of TPN. Body weight, pancreatic content, and enzyme levels in the pancreas were measured. results Compared with the control group, pancreatic wet weight was lower in all TPN groups. glucose significantly decreased the content and concentration of pancreatic protein, but amino acids did not alter the concentration of protein. The level of amylase was lower in all parenterally fed groups, with a greater decrease in the groups treated with amino acids and 30% glucose than with 50% glucose. Trypsin levels in all groups receiving TPN were markedly higher than in the control group. Conclusion TPN results in atrophy of the pancreas, but trypsin levels increase with TPN treatment. glucose elevates the amylase level in the pancreas, while amino acids suppress pancreatic amylase. Amino acids used as a source of protein maintain normal pancreatic protein levels.

关键词： amylase · exocrine pancreas · total parenteral n utrition · trypsin

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Stable isotope evidence for trophic niche partitioning in a South African savanna rodent community

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Current Zoology 2015年第3期61卷 397-411页

作者： Jacqueline CODrON Kevin J DUFFY Nico L AVENANT Matt SPONHEIMEr Jennifer LEICHLITEr Oliver PAINE Paul sandberg Daryl CODrON Institute of Systems Science Durban University of Technology Durban South Africa Karoo Palaeontology Deparlnaent National Museum PO Box 266 Bloemfontein 9301 RSA School of Mathematics Statistics and Computer Science University of KwaZulu-Natal Private Bag X01 Scottsville 3209 RSA Denartment of Mammalogv. National Museum. PO Box 266. Bloemfontein 9301. RSA Department of Anthropology University of Colorado at Boulder Boulder CO80309 USA Florisbad Quaternary research Department National Museum PO Box 266 Bloemfontein 9301 RSA

Species＇ partitioning of resources remains one of the most integral components for understanding community assem- bly. Analysis of stable carbon and nitrogen isotopes in animal tissues has the potential to help resolve patterns of partitioning be- cause these proxies represent the individual＇s diet and trophic niche, respectively. Using free-ranging rodents in a southern Afri- can savanna as a model community, we find that syntopic species within habitats occupy distinct isotope niches. Moreover, spe- cies with strongly overlapping isotope niches did not overlap in their spatial distribution patterns, suggesting an underlying effect of competitive exclusion. Niche conservatism appears to characterize the behaviour of most species in our sample - with little or no observed changes across habitats - with the exception of one species, Mastomys coucha. This species displayed a generalist distribution, being found in similar abundances across a variety of habitats. This spatial pattern was coupled with a generalist isotope niche that shifted across habitats, likely in response to changes in species composition over the same spatial gradient. The case for M. coucha supports contentions that past competition effects played a significant evolutionary role in shaping community structures of today, including the absence of strong interspecific niche overlaps within particular habitats. Our study highlights the value of stable isotope approaches to help resolve key questions in community ecology, and moreover introduces novel ana- lytical approaches to quantifying isotope niche breadths and niche overlaps that are easily comparable with traditional metrices

关键词： Competition Diet Niche breadth Niche overlap Sterkfontein Valley

Fur glowing under ultraviolet:in situ analysis of porphyrin accumulation in the skin appendages of mammals

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Integrative Zoology 2023年第1期18卷 15-26页

作者： Séverine L.D.TOUSSAINT Jasper PONSTEIN Mathieu THOUrY rémi MÉTIVIEr Daniela C.KALTHOFF Benoît HABErMEYEr roger gUILArD Steffen BOCK Peter MOrTENSEN Sverre sandberg Pierre gUErIAU Eli AMSON Ag Vergleichende Zoologie Institut für BiologieHumboldt Universität zu BerlinBerlinGermany Museum für Naturkunde Berlin Leibniz Institute for Evolution and Biodiversity ScienceBerlinGermany Ag Paläobiologie und Evolution Institut für BiologieHumboldt Universität zu BerlinBerlinGermany IPANEMA CNRSministère de la CultureUVSQMNHNUSR3461UniversitéParis-SaclayGif-sur-YvetteFrance UniversitéParis-Saclay ENS Paris-SaclayCNRSPPSMGif-sur-YvetteFrance Department of Zoology Swedish Museum of Natural HistoryStockholmSweden PorphyChem SAS DijonFrance ICMUB UMR CNRS 6302Universitéde Bourgogne Franche-ComtéFrance Norwegian Porphyria Centre(NAPOS) Haukeland University HospitalNorwegian Organization for Quality Improvement of Laboratory Examinations(Noklus)and Department of Global Public Health and Primary CareFaculty of MedicineUniversity of BergenNorway Institute of Earth Sciences University of LausanneLausanneSwitzerland Staatliches Museum für Naturkunde Stuttgart StuttgartGermany

Examples of photoluminescence(PL)are being reported with increasing frequency in a wide range of organisms from diverse ***,the chemical basis of this PL remains poorly deﬁned,and our understanding of its potential ecological function is still superﬁ*** mammals,recent analyses have identiﬁed free-base por-phyrins as the compounds responsible for the reddish ultraviolet-induced photoluminescence(UV-PL)observed in the pelage of springhares and ***,the localization of the pigments within the hair largely remains to be ***,we use photoluminescence multispectral imaging emission and excitation spec-troscopy to detect,map,and characterize porphyrinic compounds in skin appendages in *** also document new cases of mammalian UV-PL caused by free-base porphyrins in distantly related *** distribution of the UV-PL is strongly suggestive of an endogenous origin of the porphyrinic *** argue that reddish UV-PL is predominantly observed in crepuscular and nocturnal mammals because porphyrins are ***-sequently,this phenomenon may not have a speciﬁc function in intra-or interspeciﬁc communication but rather represents a byproduct of potentially widespread physiological processes.

关键词： in situ analysis mammal multispectral imaging porphyrin UV photoluminescence