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Energy calculations for manufacture of paper from logs and waste papers are reported based on data on energy use from the Canadian Census of Manufactures and estimates for collection and de-inking of waste. The energy requirement of the recycling technology explored exceeds the energy requirement of manufacture from logs by 33%. It appears that forest conservation through recycling has a fossil fuel cost.

A comparison of the field attractiveness of five samples of American-synthesized and one sample of Japanese-synthesized (Z,E)-9,11-tetradecadien-1-01 acetate (9,11-TDDA), the sex pheromone of Spodoptera littoralis Boisd. and S. litura (F.), showed that traps baited with one of the American-produced samples and the Japanese product were equally effective in attracting and capturing S. littoralis males in cotton and alfalfa fields of Israel. Optimum captures were obtained for periods up to three months with 4800 mug of 9,11-TDDA plus 8 mg of an antioxidant; higher doses were not advantageous. Paper squares were superior to two types of rubber septa and to closed polyethylene vials as dispensers for the pheromone; the polyethylene vials were least effective. In terms of numbers of moths captured, open polyethylene vials were as effective as paper dispensers when both were baited with 9-11-TDDA plus antioxidant. Admixture of (Z,E)-9,12-tetradecadien-1-o1 acetate (9,12-TDDA) with 9,11-TDDA was antagonistic at ratios of 1:20 and 1:50, but ratios from 1:500 to 1:1600 were synergistic, increasing moth catches up to 2.5-fold. Pheromone traps placed in Caesarea sand dunes located at least 3 km from the nearest host area captured larger numbers of males than traps placed in cultivated areas. It is therefore recommended that safety belts of pheromone traps, about 500 m apart, be used around cultivated areas to prevent invasion of the pest from outside and to attract males present inside such areas, thus reducing both the male population and mating through mass trapping and disruption of sex communication.

A test program was conducted to check the sensitivity and the accuracy of the hydrogen sulfide (H2S) paper tape sampler as it has been used since its introduction several years ago. Test data from this sampler were compared with those from a sampler modified by researchers from the San Francisco Bay Area Air Pollution Control District. A Mylar bag was used as a container into which laboratory air and a measured quantity of reagent-quality H2S were placed to produce a sample of known concentration. A Research Appliance Company standard G2SE sampler with a recorder was used to draw the sample from the bag and read the tape. The data show that the modifications made by the Bay Area Pollution Control District increased the sensitivity over the 0- to 60-ppb range; however, the shape of the modified curve remained the same as that of the original curve. The data also showed that the percentage accuracy remained approximately the same on both the modified and the original curves, the magnitude of the plus or min...

A mathematical programming model was formulated to determine the optimal atmospheric emission control alternatives for the pulp industry. Generalized multi-path diagrams were developed showing the emission sources, the unit emissions from these sources, and the available control alternatives. Using these diagrams it is possible to depict a given mill by selecting the appropriate flow paths. The formulation of the optimization model as a mixed integer-linear programming problem is presented. Then the results of a sample analysis using the model are described. A procedure is presented for determining the net cost of particulate emission standards as well as a sensitivity analysis of the impact on the optimal solution of varying the value of recovered chemicals.