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Book ChapterDOI

Chapter 4 – Tests for the Elements, their Ions and Compounds

01 Jan 1972-pp 94-524
About: The article was published on 1972-01-01. It has received 6 citations till now.
Citations
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Journal ArticleDOI
TL;DR: Since the mid-19th century, various pest eradication techniques have been employed on the anthropology collections at the National Museum of Natural History, Smithsonian Institution as mentioned in this paper, and these techniques are reviewed, and pesticide and fumigant use by early collectors and later collections management staff is documented.
Abstract: Since the mid-19th century, various pest eradication techniques have been employed on the anthropology collections at the National Museum of Natural History, Smithsonian Institution. These techniques are reviewed, and pesticide and fumigant use by early collectors and later collections management staff is documented. Also chronicled are the ways in which the choice of chemicals has changed over the years and the decisions that led to those changes. The effects of pest eradication techniques on the collections are discussed, and the author's findings are offered as the basis for further research.

63 citations

Journal ArticleDOI
TL;DR: In this paper, the main features, molecular structures and physical and chemical properties of these carbon types, so far as they are relevant to pigment studies, are reviewed in outline and some better-known pigments based on carbon are summarized, with an indication of which form or forms of carbon each contains.
Abstract: A primary classification of carbons is into crystalline and non-crystalline forms. The only crystalline carbon encountered as a pigment is graphite; a secondary classification for non-crystalline forms is into flame carbons (formed in the gas phase), cokes (formed in a liquid or plastic phase), chars (formed entirely in the solid phase) and natural forms such as coal. The main features, molecular structures and physical and chemical properties of these carbon types, so far as they are relevant to pigment studies, are reviewed in outline. Some better-known pigments based on carbon are summarized, with an indication of which form or forms of carbon each contains. X-ray diffraction patterns for graphites, and for examples of the non-crystalline types, are described and discussed. Particle morphology of various carbons and pigments, as elucidated from scanning electron micrographs, is described in some detail, and notes are added on the use of optical microscopy in studying these materials.

48 citations

Journal ArticleDOI
TL;DR: In this paper, the Freer collection of Japanese paintings of the twelfth to the sixteenth centuries has been determined, and basic lead carbonate (lead white) was found in 12 out of 13 Chinese paintings and in all three Korean paintings.
Abstract: Japanese paintings of the twelfth to the sixteenth centuries in the collection of the Freer Gallery of Art has been determined. In 12 out of 13 Chinese paintings, and in all three Korean paintings, basic lead carbonate (lead white) was found. Of the 29 Japanese paintings, six had basic lead carbonate, 20 had basic lead chloride (which occurred as two different compounds), and two carried both of these species. One Chinese painting had lead sulphate and one Japanese painting lead phosphate. Historical evidence suggests that two forms of 'lead white' were known and distinguished during the eighth century in Japan; the possible connection between this and the present findings on Japanese paintings is discussed.

16 citations

Journal ArticleDOI
TL;DR: The outlook and likely impact of these tests on the expansion of scientific investigation and legacy and technical details of selected spot tests used in solving crime are described.
Abstract: Chemical spot tests are one of the oldest and simplest presumptive methods of analytical chemistry. They are an integral part of the schematic analysis of different types of substances in various pure and applied scientific disciplines including forensic science. The role of spot tests has remained eternal utility in different branches of forensic science to analyze various types of physical or trace evidences. Forensic experts need to have an absolute understanding of the foundation and technicality behind complex reactions of customary spot tests. Forensic science literature dwells in the diversity of spot tests but an informative and comprehensive compendium of such prose remains occasional and limited in general. Keeping in view the ample history and legacy of spot test, the current review was constructed from a core of historical literature to recapitulate trending applications, chemistry, and limitations of notable "Griess test", "Luminol test", "Kastle-Meyer test", "Phenolphthalein test", "Ninhydrin test", and "Spy dust" in forensic science. The aim of this review article was to describe the outlook and likely impact of these tests on the expansion of scientific investigation. The anticipated output of this review is supposed to impart compatible knowledge in the attentive readers interested in understanding legacy and technical details of selected spot tests used in solving crime.

7 citations

Journal ArticleDOI
TL;DR: In this article, the corrosion products on a silver dragon suspected to have been treated with cyanide revealed both silver cyanide and chalconatronite, which can be formed on silver objects cleaned or replated using a cyanide solution.
Abstract: Analysis of the corrosion products on a silver dragon suspected to have been treated with cyanide revealed both silver cyanide and chalconatronite. It appears that both of these corrosion products can be formed on silver objects cleaned or replated using a cyanide solution. These corrosion products darken with exposure to light; therefore, they may be mistaken for silver sulfide. In order to determine how to remove the highly poisonous cyanide corrosion product, numerous tests were run. Using a carefully timed procedure the silver cyanide was removed with an aqueous solution of 20% sodium thiosulfate. The chalconatronite was removed mechanically.

5 citations

References
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Journal ArticleDOI
TL;DR: In this paper, the authors describe a scenario where the average PVA is 0.25% and 0.2% of the PVA's PVA values are due to a single PVA.
Abstract: チタンはモーリンと弱酸性で反応して橙色の難溶性錯塩を生成する.このものはポリビニルアルコール(PVA)により分散されて溶液は透明になり,吸光度も長時間安定である.これを利用してチタンの定量をおこなった.定量操作はつぎのとおりである.すなわち,試料溶液に重合度が1200程度以上のPVAの0.25%溶液を3ml,0.2%モーリン溶液を1ml加えたのち水で約15mlとし,水酸化ナトリウムで予備中和をおこない,10N酢酸2.5mlを加え,25mlのメスフラスコに移して水で定容とする.420mμの吸光度を水を対照として測定する.1~50μgのチタンの定量が可能である.なおこの錯塩は,エチルアルコールを約30%以上共存させると溶解し透明溶液が得られるが,この場合の吸光度はpHの影響を大きく受け利用するのは困難である.

2 citations

Journal ArticleDOI
TL;DR: In this paper, the authors propose a method to improve the quality of the data collected by the data collection system, which is based on the concept of "transparency" and "compensated data".
Abstract: ジエチルジチオカルバミン酸亜鉛の四塩化炭素溶液で銅を抽出し比色定量する方法について検討した.本法は鉄,コバルト,ニッケル,ビスマスによって呈色したが,その妨害はジエチルジチオカルバミン酸ナトリウムを用いた場合よりはるかに少なく,簡易な定量法としてすぐれていた.またこれらの妨害イオンに影響されない定量法として,つぎの方法を試み好結果を得た.すなわち酸性溶液で銅をジチゾンの四塩化炭素溶液で抽出し,四塩化炭素層をビスハイドロキシエチルジチオカルバミン酸亜鉛の水溶液とふりまぜると,銅はその銅塩となって定量的に水層に移行した.ついで水層をジエチルジチオカルバミン酸亜鉛の四塩化炭素溶液で抽出すれば,銅はギエチルジチオカルバミン酸銅なってふたたび四塩化炭素層に移行した.この四塩化炭素層の吸光度を光電比色計を用いて測定し銅を定量した.

2 citations

Journal ArticleDOI
TL;DR: In this paper, a zweiwertiges Nickel with Kaliumperoxydisulfat bei 24-25° in alkalischer Losung, so bildet sich beim Zerfall des zuerst entstandenen, unbestandigen NiO2 · x H2O das krystalline, ziemlich bestandige Ni2O3 · x h2O=2 NiOOH · (x-1)H2O.
Abstract: Oxydiert man zweiwertiges Nickel mit Kaliumperoxydisulfat bei 24–25° in alkalischer Losung, so bildet sich beim Zerfall des zuerst entstandenen, unbestandigen NiO2 · x H2O das krystalline, ziemlich bestandige Ni2O3 · x H2O=2 NiOOH · (x-1)H2O. Durch Trennung des letzteren aus seiner Mutterlauge und darauffolgendes Losen in Saure bei Gegenwart von Kaliumjodid wird eine dem Nickel aquivalente Menge Jod freigemacht. Durch Titrieren desselben mit Thiosulfat last sich sodann die Menge des Nickels bestimmen.

2 citations

Journal ArticleDOI
TL;DR: In this paper, a Verfahren zur colorimetrischen Wismutbestimmung beschrieben, bei dem der mit Caprolactam-and Kaliumjodid-Uberschus erzeugte Niederschlag mit Chloroform aus der wasrigen Phase extrahiert wird.
Abstract: Es wird ein Verfahren zur colorimetrischen Wismutbestimmung beschrieben, bei dem der mit Caprolactam- und Kaliumjodid-Uberschus erzeugte Niederschlag mit Chloroform aus der wasrigen Phase extrahiert wird. Die Extinktion der durch Zusatz von Aceton geklarten organischen Phase wird bei 420 nm gemessen. 20–200 μg Bi konnen nach diesem Verfahren auch in Gegenwart nicht zu groser Uberschusse an Pb, Zn, Cd, Mg, Fe und Cu auf 2–5% genau bestimmt werden. Hg2+-, Sb3+- und Cl−-Ionen storen.

2 citations