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INSECT STING ANAPHYLAXISAbstract. Anaphylaxis to insect stings has occurred in 3% of adults and can be fatal even on the first reaction. Large local reactions are more frequent but rarely dangerous. The chance of a systemic reaction to a sting is low (5–1. Venom skin tests are most accurate for diagnosis but the RAST is an important complementary test. ![]() European Union agency responsible for the protection of public and animal health through the scientific evaluation and supervision of medicines.The degree of sensitivity on skin test or RAST does not reliably predict the severity of a sting reaction. Venom sensitization can be detected in 2. Venom immunotherapy is 7. Most patients can discontinue treatment after 5 years, with very low residual risk of a severe sting reaction. ![]() Retrouvez toutes les discothèque Marseille et se retrouver dans les plus grandes soirées en discothèque à Marseille. General notation: ND = Not Documented. Select ND when there is no documentation in the medical record to explain why a treatment or intervention is not performed. ![]() Keywords: anaphylaxis, venom, insect sting, Hymenoptera, immunotherapy. Stinging insects of the order Hymenoptera can cause systemic allergic reactions including anaphylaxis, but such reactions are rare with biting insects. This review will describe the clinical patterns and treatment of sting reactions, which how they may resemble or differ from other causes of anaphylaxis. CLINICAL FEATURESTransient pain, itching and swelling are normal responses to stings, but allergic reactions can cause more severe local reactions or generalized systemic reactions. Large local sting reactions cause delayed and prolonged local inflammation increasing over 2. These reactions resemble “late phase reactions” which are Ig. E dependent. Most patients with large local reactions patients have detectable venom- specific Ig. E.(1)Systemic (generalized) reactions may cause any one or more of the signs and symptoms of anaphylaxis. Although the definition of anaphylaxis would seem to exclude reactions involving only cutaneous manifestations (urticaria, angioedema, pruritus, flush), these are included in this review because they must be considered in diagnosis and treatment of insect allergy as potential precursors of more severe anaphylactic reactions.(2) There are also reports of chronic urticaria and cold urticaria developing after insect stings, usually without any immediate hypersensitivity reaction, and with uncertain risk of anaphylaxis to a future sting.(3) Unusual patterns of reaction have also been reported including nephropathy, central and peripheral neurologic syndromes, idiopathic thrombocytopenic purpura, and rhabdomyolysis, but most of these are not Ig. E related.(4,5)Systemic (generalized) allergic sting reactions result in cutaneous, vascular or respiratory symptoms and signs, either singly or in any combination, with possible involvement of other less common target tissues. Cardiac anaphylaxis can also cause bradycardia, arrhythmias, angina or myocardial infarction. Abdominal cramps are not uncommon, and “spontaneous abortion” can occur as a result of sting anaphylaxis. There may be a greater chance of systemic reaction if there are multiple stings at one time, or if there are repeated stings in the same summer. In contrast to food anaphylaxis, the slower the onset of the sting reaction, the less likely it is to be life- threatening.(6,7)Whether anaphylaxis differs clinically between children and adults is unclear for most causes, but is known for insect sting allergy. Cutaneous symptoms are most common overall, affecting 8. Almost 5. 0% of reactions in both children and adults included respiratory complaints. Symptoms and signs of hypotension were uncommon in children but occurred in over 6. The clinical presentation can be vague and uncertain both during the reaction and in the history. To aid proper diagnosis and treatment, objective documentation should be made whenever possible, including description of cutaneous findings, vital signs, pulse oximetry and air flow measurements. Treatment of insect sting anaphylaxis is no different from other causes of anaphylaxis.(1. Biphasic and protracted anaphylaxis have been reported with insect stings, so medical observation should extend for 3 to 6 hours depending on severity. Some individuals are resistant to epinephrine, especially those on beta- blocker medication. Nevertheless, the risk of stopping beta- blockers in patients with cardiac disease may exceed the risk of continuing the drugs.(1. Patients discharged from emergency care of anaphylaxis should receive instruction about the need for an epinephrine kit, an allergy consultation and preventative treatment, and should understand that using the kit is not a substitute for emergency medical attention.(1. ETIOLOGYStinging insects of the order Hymenoptera are the main cause of insect- related anaphylaxis. There are 3 families of Hymenoptera with clinical importance: the bees (honeybees, bumblebees), vespids (yellow jackets, hornets, wasps), and stinging ants (genus Solenopsis and others). Exposure to these insects is affected by environmental and ecological factors. The africanized honeybee (“killer bee”) is an aggressive hybrid resulting from an experiment intended to enhance honey production. The danger from the africanized honeybee stems from the numbers of stings because of swarm- and- attack behavior. Their venom is actually no different than that of other honeybees. Imported fire ants arrived almost 1. Mobile, Alabama, and have rapidly become an increasing public health hazard in the south and southeast parts of the United States.(1. There have been increasing reports of anaphylaxis due to other species of stinging ants in Asia and Australia.(1. The immunochemical characteristics and immunogenetic relationships of the Hymenoptera venoms have been thoroughly studied.(1. Venoms contain multiple protein allergens, most having enzymatic activity. Honeybee venom is immunochemically distinct from the other Hymenoptera, but vespid venoms have a high degree of cross reactivity with each other and contain essentially the same allergens. Skin tests are positive to all 3 of the common vespid skin test preparations (yellow jacket, yellow hornet, white- faced hornet) in most vespid allergic patients. Polistes wasps are not as closely related to the other vespids, and only 5. Fire ant venoms are different in that they contain very little protein, in a suspension of alkaloid toxins that causes the characteristic vesicular eruption. The proteins in fire ant venoms are antigenically unique except for one that shows limited cross reactivity with a vespid allergen. The diagnostic and therapeutic materials currently supplied by commercial laboratories are fire ant whole body extracts which, unlike the other insect whole body extracts, do show reasonable allergenic activity for diagnostic skin testing and for preventative immunotherapy.(1. EPIDEMIOLOGY/NATURAL HISTORYKnowledge of the epidemiology and natural history of Hymenoptera venom sensitivity is crucial in clinical decision- making. It was the lack of this information that prolonged the mistaken conclusion that whole body extract therapy was effective in the prevention of anaphylaxis.(2. The studies of whole body extract were not placebo controlled, and included children, large local reactors, mild systemic reactors, and individuals who had negative venom skin tests, all of whom are now known to have very low risk of anaphylaxis to stings. Insect sting allergy can occur at any age, often following a number of uneventful stings, and is more common than previously thought. Systemic allergic reactions are reported by up to 3% of adults, and almost 1% of children have a medical history of severe sting reactions.(2. The frequency of large local reactions is uncertain, but is estimated at 1. At least 5. 0 fatal sting reactions occur each year in the United States.(6) Half of all fatal reactions occur with no history of previous sting reactions. Many sting fatalities may be unrecognized. It is possible to document in some postmortem blood samples, the presence of both venom- specific Ig. E antibodies as well as elevated serum tryptase suggesting a possible fatal sting reaction in some cases of unexplained sudden death.(2. However the presence of Ig. E antibodies to Hymenoptera venom is not, in itself, unusual. Over 3. 0% of adults stung in the previous 3 months showed venom- specific Ig. E by skin test or RAST, and over 2. Venom sensitivity in asymptomatic adults is often transient, disappearing more rapidly than it does in patients with a history of anaphylaxis. Of the subjects with initial positive skin tests, 3. Those who remained positive showed a 1. Systemic reactions can become progressively more severe with each sting in some cases, but this seems to be the exception rather than the rule. Call of Duty: Black Ops. Call of Duty: Black Ops is a first- person shooter video game,[5] developed by Treyarch and published by Activision. Announced on April 3. November 9, 2. 01. Microsoft Windows, Play. Station 3, Xbox 3. Wii consoles,[7] with a separate version for Nintendo DS developed by n- Space.[8] It is the seventh title in the Call of Duty series and the third to be developed by Treyarch. It serves as the sequel to Call of Duty: World at War.[9]Set in the 1. Cold War, the game's campaign follows CIA operative Alex Mason as he attempts to recall certain memories in combat in order to locate a numbers station, which is due to transmit broadcasts to sleeper agents who are bound to use chemical weapons across the United States. Mason and CIA operative Jason Hudson are the game's main playable characters, as well as Red Army soldier Viktor Reznov in only one mission. Locations featured in the game include Cuba, Russia, Vietnam, and the Arctic Circle. The multiplayer of Black Ops features multiple objective- based game modes that are playable on 1. Improvements to loadout options and killstreak rewards are made. A form of virtual currency, COD Points, allows players to purchase weapons and customization options for their in- game character, as well as attachments and customization options for their weapon. Development for the game began in 2. It runs an enhanced version of the IW 3. Treyarch's past title, World at War. The improvements made allowed for bigger campaign levels to be made as well as enhanced lighting. Treyarch focused specifically on Black Ops during development. Different teams within the company focused on a certain game mode. Music was composed by Sean Murray, with music by the Rolling Stones and Creedence Clearwater Revival appearing in the campaign. Marketing of the game began in April 2. Multiple trailers promoting the game and its modes were released from May until October. Within 2. 4 hours of going on sale, the game had sold more than 5. U. S. and 1. 4 million in the UK, breaking the record set by its predecessor Modern Warfare 2 by some 2. After six weeks on release, Activision reported that Black Ops had exceeded $1 billion in sales.[1. On August 3, 2. 01. Activision confirmed that the game had sold over 2. US, UK and Europe.[1. A sequel, Call of Duty: Black Ops II, was released on November 1. Call of Duty: Black Ops III was released on November 6, 2. Black Ops II. Gameplay[edit]Black Ops is a first- person shooter, retaining the same gameplay mechanics as previous Call of Duty titles. Call of Duty: Black Ops is a first-person shooter video game, developed by Treyarch and published by Activision. Announced on April 30, 2010, it was released. · PC vs Console: which is better; Why console 30fps feels smooth compared to on pc? Why do games run smoother on consle than PC? Games stuck at 30fps. The latest PC gaming hardware news, plus expert, trustworthy and unbiased buying guides. ![]() ![]() 2017: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2016: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2015: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2014. The player assumes the role of a foot soldier who can wield various firearms (only two of which can be carried at once), throw grenades and other explosives, and use other equipment as weapons. A player close enough to an enemy can kill with one knife blow. A character can take three stances: standing, crouching or prone. Each affects rate of movement, accuracy, and stealth. The player can drop to the prone stance from the standing stance while running (colloquially known as "dolphin diving"), and can momentarily sprint before having to stop. The screen glows red to indicate damage to a player's health, which regenerates over time. When the character is within the blast radius of a live grenade, an on- screen marker indicates where it is in relation to the player, helping the player to move away or to throw it back. Among the weapons new to the series in Black Ops are crossbows with bolts and explosive ammunition, Dragon's Breath rounds and ballistic knives. The player assumes the role of various characters during the single- player campaign, changing perspectives throughout the story. The playable characters are special forces operatives conducting black operations behind enemy lines. In this way, the player's characters have their own traits such as voices and shadows.[9] Each mission features a series of objectives that are displayed on the heads- up display, which marks the direction and distance towards and from such objectives as it has been in the earlier versions. The player is accompanied by friendly troops throughout the game. Although primarily a first- person shooter, certain levels feature sequences where the player pilots a Hind helicopter and guides friendly troops from a SR- 7. Blackbird reconnaissance aircraft.[1. The campaign features several scripted cinematic moments. One of them is a bullet time effect during the "Victor Charlie" level, activated when the player fires toward the last enemy of a Viet Cong squad.[citation needed]As a first in the Call of Duty main series, player characters can now speak during gameplay, whereas in previous installments, primarily those made by Infinity Ward, characters would be silent during gameplay, even if they could speak during cutscenes. Multiplayer[edit]. Players can customize their weaponry in the game, as seen with this customized FAMAS. The online multiplayer mode of Black Ops usually revolves around two teams on a specific mission. For example, in Team Deathmatch the team with the most kills wins, while in Capture the Flag, players take the other team's flags and return it to their own base. Additionally, there is Free For All in which players aren't separated into teams. Not including Downloadable maps, there are 1. Black Ops retains the experience points and unlockable reward system that has been kept since Call of Duty 4. The game's multiplayer focuses on socialization and customization.[9] "Create- a- Class 2. Even reticles can be modified. There are more than one style for an attachment, which allows for a lot more personalized weaponry; for example, the player can choose between a red dot sight or a reflex sight, both of which share many of the same traits, although the red dot fills up less of the screen (something desired by many players). Character models depend on the first tier perk instead of the weapon's type. Furthermore, face paints can be unlocked. New custom killstreak rewards include explosive R/C cars, guided missiles and controllable attack helicopters.[2. A currency system has been implemented allowing players to buy weapons, accessories and clothes. Players can gamble with their "COD Points" in a free- for- all based playlist called "Wager Match", which is composed of four game modes.[2. Time limited objectives known as "Contracts" can be purchased to gain more currency and experience points. The progression system is not featured in local split- screen multiplayer. In local split- screen play, all character customization options are already unlocked. Players can no longer define game rules such as win conditions. Players can play alone or with friends against AI opponents in "Combat Training" with a separate progression system.[2. Online split- screen is re- introduced on Xbox 3. PS3. The guest account can rank up but is reset after each sign out. Only on Xbox 3. 60, a second Gold Xbox Live account can be used to keep the second player's progression.[2. Aside from the Combat Training mode, Xbox users can also have up to four players in split- screen mode play against AI opponents even without having an Xbox Live account. This is done by configuring the Local Split Screen settings and setting the number of enemies to a value greater than zero.[2. For the first time in the series, clips from online gameplay can be recorded. Some specific features that have been removed from the PC version of Infinity Ward's Modern Warfare 2 return, such as lean,[2. Dedicated servers are exclusively provided by Game Servers.[3. Steam is the exclusive platform for Black Ops on PC, and the game is protected by Valve Anti- Cheat.[3. The Wii version of the game includes in- game voice chat. This is the first Call of Duty title to include the voice chat feature for the Wii. Nintendo and PDP have partnered to release the first headset to be used with the Wii known as PDP's Headbanger Headset.[3. Zombies[edit]A zombie cooperation mode, titled "Zombies", is included in the game. Originally featured in World at War, it was revamped to be included in Black Ops.[3. It is a four- player online and two- player split screen co- op mode (which can also be unlocked online). Based on the original game, in the map "Five", players take the roles of John F. Kennedy, Richard Nixon, Robert Mc. Namara, and Fidel Castro as they fight zombies at The Pentagon.[3. Ti. Vo DVRs & Hard Drive Recorders. DVRs, Hard Drive Recorders└ TV, Video & Home Audio└ Consumer Electronics. All Categories. Antiques. Art. Baby. Books. Business & Industrial. Cameras & Photo. Cell Phones & Accessories. Clothing, Shoes & Accessories. Coins & Paper Money. Collectibles. Computers/Tablets & Networking. Consumer Electronics. Crafts. Dolls & Bears. DVDs & Movies. Entertainment Memorabilia. 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![]() ![]() Sexually Active Old People Seem to Be Smarter. Fucking is good. What else can you say? We’re a species that gets to actually enjoy sexual activity. It makes babies. When consenting adults do sex- making, it is good. A new study suggests that when old people do sex, it is also good. Maybe even more good. ![]() Mazda does this by using what it calls “ring structures”. This means energy from combustion can be more efficiently translated into work done on the piston. The researchers behind a new study already knew that increased mental, social, and physical activity is associated with less cognitive decline. So, they posit, seeing as sex consists of mental, social, and physical activity, more sexing must also mean better thinking. The study only had 7. The study recruited the frisky folks through “adverts disseminated by local community networks.” Each old person answered survey questions about their sexual activity frequency from the past twelve months, where “sexual activity was defined as engagement in sexual intercourse, masturbation, or petting/fondling,” according to the study. That’s also how I define it, by the way. The researchers also asked questions about their participant’s educations, gender, and cardiovascular health, as well as other factors like their social wellbeing. Then, the older crew performed tests of their attention, memory, and other cognitive abilities. Ultimately, the study finds that the ability to articulate oneself, and the ability to determine how objects relate to each other in space increased the more people performed sexual acts. Hell yeah!!! Does the study have limitations? Of course it does. The authors point out that 7. They also don’t differentiate between different kinds of sexual activity. This field of study is still relatively young, and we plan to address such details in our subsequent research,” they write. Finally, and I’m so glad they point all these limitations out, it’s not a controlled experimental study, just a survey. We cannot infer a causal relationship between SA and cognitive function,” just that the people who had better cognitive abilities also said that they boned more. Maybe they bone more because they’re smarter, for all we know. The study does have another thing going for it, though: it’s a replication study of another one performed by the same team last year. So, honestly, fuck it, grandmas and grandpas of the world. By “it,” I mean each other.[Journals of Gerontology]. Install Vmware Tools Fedora 13 Linux Live MediaServer World - Build Network Server. Hello everyone, and welcome to the unofficial list of which OSes work and which don't in Microsoft Virtual PC 2004. I hope this site helps you! [This message comes from the desk of the Fedora Project Leader directly. Happy release day! — Ed.] Hi everyone! I’m incredibly proud to announce the immediate. We offer open-source (Linux/Unix) virtual machines (VMDKs) for VMware Player/Plus/Workstation, we install and make them ready-to-use VMware images for you. From here. ![]() The fatigue crack growth and fatigue life prediction are essentials for the reliable lifespan of an engineering structure. In computational analysis, the most.Solder - Wikipedia. This article is about the material. For the process, see Soldering. A soldered joint used to attach a wire to the pin of a component on the rear of a printed circuit board. Spool of solder, 1. Solder (,[1][1] or in North America [2]) is a fusible metal alloy used to create a permanent bond between metal workpieces. The word solder comes from the Middle English word soudur, via Old Frenchsolduree and soulder, from the Latinsolidare, meaning "to make solid".[3] In fact, solder must be melted in order to adhere to and connect the pieces together, so a suitable alloy for use as solder will have a lower melting point than the pieces it is intended to join. Whenever possible, the solder should also be resistant to oxidative and corrosive effects that would degrade the joint over time. Solder that is intended for use in making electrical connections between electronic components also usually has favorable electrical characteristics. Soft solder typically has a melting point range of 9. C (1. 90 to 8. 40 °F; 3. K),[4] and is commonly used in electronics, plumbing, and sheet metal work. Manual soldering uses a soldering iron or soldering gun. Alloys that melt between 1. C (3. 60 and 3. 70 °F; 4. K) are the most commonly used. Soldering performed using alloys with a melting point above 4. Marc is a powerful, general-purpose, nonlinear finite element analysis solution to accurately simulate the product behavior under static, dynamic and multi-physics. C (8. 40 °F; 7. 20 K) is called "hard soldering", "silver soldering", or brazing. In specific proportions, some alloys can become eutectic — that is, their melting point is the same as their freezing point. Non- eutectic alloys have markedly different solidus and liquidus temperatures, and within that range they exist as a paste of solid particles in a melt of the lower- melting phase. In electrical work, if the joint is disturbed in the pasty state before it has solidified totally, a poor electrical connection may result; use of eutectic solder reduces this problem. The pasty state of a non- eutectic solder can be exploited in plumbing, as it allows molding of the solder during cooling, e. For electrical and electronics work, solder wire is available in a range of thicknesses for hand- soldering, and with cores containing flux. It is also available as a paste or as a preformed foil shaped to match the workpiece, more suitable for mechanized mass- production. Alloys of lead and tin were commonly used in the past and are still available; they are particularly convenient for hand- soldering. Lead- free solders have been increasing in use due to regulatory requirements plus the health and environmental benefits of avoiding lead- based electronic components. They are almost exclusively used today in consumer electronics.[5]Plumbers often use bars of solder, much thicker than the wire used for electrical applications. Jewelers often use solder in thin sheets, which they cut into snippets. ![]() Lead- free solder[edit]. Soldering copper pipes using a propane torch and lead- free solder. Mechanical engineering is the discipline that applies engineering, physics, and materials science principles to design, analyze, manufacture, and maintain mechanical. International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research. On July 1, 2. 00. European Union. Waste Electrical and Electronic Equipment Directive (WEEE) and Restriction of Hazardous Substances Directive (Ro. HS) came into effect prohibiting the inclusion of significant quantities of lead in most consumer electronics produced in the EU. In the US, manufacturers may receive tax benefits by reducing the use of lead- based solder. Lead- free solders in commercial use may contain tin, copper, silver, bismuth, indium, zinc, antimony, and traces of other metals. Most lead- free replacements for conventional 6. Sn- Pb solder have melting points from 5 to 2. C higher,[6] though there are also solders with much lower melting points. It may be desirable to use minor modification of the solder pots (e. Lead- free solder may be less desirable for critical applications, such as aerospace and medical projects, because its properties are less thoroughly known. Tin- Silver- Copper (Sn- Ag- Cu, or "SAC") solders are used by two- thirds of Japanese manufacturers for reflow and wave soldering, and by about 7. The widespread use of this popular lead- free solder alloy family is based on the reduced melting point of the Sn- Ag- Cu ternary eutectic behavior (2. C), which is below the 2. Sn- Ag (wt.%) eutectic of 2. C and the 5. 9/4. Sn- Cu eutectic of 2. C (recently revised by P. Snugovsky to 5. 3/4. Sn- Cu). The ternary eutectic behavior of Sn- Ag- Cu and its application for electronics assembly was discovered (and patented) by a team of researchers from Ames Laboratory, Iowa State University, and from Sandia National Laboratories- Albuquerque. Much recent research has focused on selection of 4th element additions to Sn- Ag- Cu to provide compatibility for the reduced cooling rate of solder sphere reflow for assembly of ball grid arrays, e. Tin- Silver- Copper- Zinc (Sn- Ag- Cu- Zn) (melting range of 2. C) and 1. 8/6. 4/1. Tin- Silver- Copper- Manganese (Sn- Ag- Cu- Mn) (melting range of 2. C). Tin- based solders readily dissolve gold, forming brittle intermetallics; for Sn- Pb alloys the critical concentration of gold to embrittle the joint is about 4%. Indium- rich solders (usually indium- lead) are more suitable for soldering thicker gold layer as the dissolution rate of gold in indium is much slower. Tin- rich solders also readily dissolve silver; for soldering silver metallization or surfaces, alloys with addition of silvers are suitable; tin- free alloys are also a choice, though their wettability is poorer. If the soldering time is long enough to form the intermetallics, the tin surface of a joint soldered to gold is very dull.[7]Lead solder[edit]Tin- lead (Sn- Pb) solders, also called soft solders, are commercially available with tin concentrations between 5% and 7. The greater the tin concentration, the greater the solder’s tensile and shear strengths. Historically, lead has been widely believed to mitigate the formation of tin whiskers, though the precise mechanism for this is unknown.[8] Today, many techniques are used to mitigate the problem, including changes to the annealing process (heating and cooling), addition of elements like copper and nickel, and the inclusion of conformal coatings.[9] Alloys commonly used for electrical soldering are 6. Sn- Pb, which melts at 1. C (3. 70 °F),[1. 0] and 6. Sn- Pb used principally in electrical/electronic work. C or 3. 61 °F) of all the tin- lead alloys; andthe melting point is truly a point — not a range. In the United States, lead is prohibited in solder and flux in plumbing applications for drinking water use, per the Safe Drinking Water Act (SDWA).[1. Historically, a higher proportion of lead was used, commonly 5. This had the advantage of making the alloy solidify more slowly. With the pipes being physically fitted together before soldering, the solder could be wiped over the joint to ensure water tightness. Although lead water pipes were displaced by copper when the significance of lead poisoning began to be fully appreciated, lead solder was still used until the 1. The electrochemical couple of copper and lead promotes corrosion of the lead and tin. Tin, however, is protected by insoluble oxide. Since even small amounts of lead have been found detrimental to health,[1. Lead- free solder.)The addition of tin—more expensive than lead—improves wetting properties of the alloy; lead itself has poor wetting characteristics. High- tin tin- lead alloys have limited use as the workability range can be provided by a cheaper high- lead alloy.[1. Before recent requirements for lead- free products, electronic components on printed circuit (printed wiring) boards (PCBs) were connected to the etched- copper- foil circuit, and hence to other components, by soldered joints created either by hand with a soldering iron using flux- core eutectic or near- eutectic (6. However, boards using the finest- pitch surface mount technology usually use solder paste applied to each location to be soldered before the component is placed on the board. Lead- tin solders readily dissolve gold plating and form brittle intermetallics.[7] 6. Sn- Pb solder oxidizes on the surface, forming a complex 4- layer structure: tin(IV) oxide on the surface, below it a layer of tin(II) oxide with finely dispersed lead, followed by a layer of tin(II) oxide with finely dispersed tin and lead, and the solder alloy itself underneath.[1. Lead, and to some degree tin, as used in solder contains small but significant amounts of radioisotope impurities. Radioisotopes undergoing alpha decay are a concern due to their tendency to cause soft errors. Polonium- 2. 10 is especially problematic; lead- 2. Uranium- 2. 38 and thorium- 2. |
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