The research on ammonia dissolving after thermal dissociation and direct ammonia dissolving shows that APT solid is thermally dissociated for 50 minutes at temperature of 280±5℃, and then 1:3 ammonia solution of 200 mL is added to dissolve for 6 hours at temperature of 95℃, leaching efficiency is 85.1%. Dissociation time has a little influence on S (Fe)/WO3. Leaching efficiencyof ammonia dissolving after thermal dissociation is higher than that of direct ammonia dissolving, but amounts of S ( Fe ) / WO3are basically similar.

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The new process of calcine for ammonium paratungstate to tungsten trioxide by microwave was investigated. The results of experiment show that the maximum decomposing rate of ammonium paratungstate is 96 .67 % after 4 min bymicrowave heating. In the new calcining process, the primary influnce factor is ammonium paratungstate' s weight, the secondary factors are time and microwave power. In this experiment range, the optimum conditions are that the microwave power is 650 W, the calcining time is 4 min, and the ammonium paratungstate′s weight is 10g .

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A series of WO3 catalysts were obtained through pyrolysis of ammonium paratungstate under different O2/Ar at 700℃. The catalysts were identified by XRD, XPS, DRS measurements, and the photo catalytic activity of WO3 for O2 evolution was studied. The results indicate that with the increasing content of Ar, the oxygen vacancies of WO3 catalysts are increased, the photo catalytic activity for O2 evolution is advanced and the photo catalytic activity of WO3 obtained in pure Ar is the highest. The influence of Fe2+ on photo catalytic activity for O2 evolution was also investigated. The results show that the activity of WO3 is restrained by Fe2+in the photo catalytic reaction with Fe3+as electron acceptor.

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Matches usually start from 501 in competition darts but other common starts are 301, 401, 701, and even 1001. Sometimes darts matches are played where a “double” is required to start each “Leg” of the match. However, the most common form of play is “straight start” which means that players/teams can begin to score points immediately with the first darts game thrown. Both teams start on the agreed starting number and the object is to score down to zero as quickly as possible. The value of the different sectors of the dartboard can be seen in Fig 1. above. Each section or “leg” of the match must be finished with a “double”, this means the outer scoring ring. For example as one approaches the end of a “leg” a player or team may have 40 points left to score. This means Double 20 is required and to end the “Leg” a dart must be thrown into the “double” section of the “20” sector. Should the thrower miss “double” 20 and hit (for example) a single 1, the the thrower would require 39 to win the “leg” where a single 7 then “double” 16 could be an option. Another example could be the player or team require 51 points. Then there would be several alternatives to end the “leg”. The usual route would be either a single 11 and then “double” 20, or perhaps a single 19 and then “double” 16. The first player or team to hit the required “double” wins the “leg”. A new leg is then started and the procedure repeated until one of the players or teams has won the required number of “legs” to win darts game.

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