Rates of evaporation of water through compressed monolayers on water     

Irving Langmuir  Vincent J. Schaefer 《Journal of The Franklin Institute》1943,235(2):119-162

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Science calls to youth: by Raymond F. Yates. 205 pages,illustrations, 14 × 20 cms. New York. D. Appleton-Century Company, 1941. Price $2.00.     

J. Hublfy Schall 《Journal of The Franklin Institute》1942,233(5):512

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The dielectric properties of resin-oil mixtures     

J.B. WhiteheadJ.J. Chapman 《Journal of The Franklin Institute》1941

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The elimination of hypo from photographic images     

J.I. Crabtree  G.T. Eaton  L.E. Muehler 《Journal of The Franklin Institute》1940,230(6):701-725

It is very difficult, if not impossible, to remove the last traces of hypo from photographic papers by any known procedure of washing. The sulfur in the residual hypo ultimately, and especially under abnormal conditions of temperature and humidity, combines with the silver image to form yellowish brown silver sulfide. This phenomenon is known as sulfiding or “fading” of the image. The various factors which affect the rate of fading of images and the washing out of hypo from films and papers are outlined.Chemical methods of hypo elimination have been proposed from time to time but the majority of these have not been satisfactory because they tend to leave substances such as thionates in the photographic material, which are equally as difficult to wash out as hypo and which also tend to sulfide or fade the silver image. A new hypo eliminator is recommended consisting of two volatile chemicals, hydrogen peroxide and ammonia. This eliminator oxidizes the hypo to sodium sulfate, which is inert and soluble in water, while any excess eliminator evaporates on drying.Two formulas and treatments are proposed: (1) Complete elimination of hypo for use by the professional, advanced amateur, and photofinisher who demand the highest standard of photographic quality in their prints.(2) Almost complete elimination of hypo (less than o.oi milligram per square inch).Since the conditions to which prints will be subjected are rarely known in advance, use of the “complete elimination treatment” is advised in all cases.  相似文献   

Teaching St. John's Gospel     

J.T. Christine M.A. 《British Journal of Religious Education》1940,7(2):96-99

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The distribution of radiophosphorus and radiogold in rats after oral,intraperitoneal and subcutaneous administration     

J.O. Ely 《Journal of The Franklin Institute》1940,230(1):125-130

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On the geometry of optical indicators     

Kalman J. DeJuhasz 《Journal of The Franklin Institute》1940,229(1):53-80

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Measurement of light from a tellurium vapor arc     

J.W. Marden  N.C. Beese  George Meister 《Journal of The Franklin Institute》1938,225(1):45-52

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Force transducer system for measurement of ice hockey skating force     

Tyler J. Stidwill  Rene Albert Turcotte  Phil Dixon  David J. Pearsall 《Sports Engineering》2009,12(2):63-68

The purpose of this study was to develop a portable force measurement system for ice hockey skating. The system consisted of three strain gauge pairs affixed to an ice hockey skate’s blade holder with wire leads connected to a microprocessor controlled data acquisition device carried in a backpack worn by the skater. The configuration of the strain gauges simultaneously determined the vertical and medial–lateral force components experienced by the blade holder with a resolution accuracy of 1.9 N and a coefficient of variation of 9.2%. On-ice testing of this system with subjects performing forward start, acceleration, and constant velocity skating permitted unencumbered, natural movement and demonstrated clear, unambiguous signal responses, high trial-to-trial repeatability, and easy data retrieval. The practicality and accuracy of this testing approach have many applications, such as a quantitative tool for skating force assessment to aid athletes and coaches, as well as providing the means to examine other skill-specific dynamics.  相似文献   

Understanding the role of shaft stiffness in the golf swing   总被引：3，自引：3，他引：0  

Sasho James MacKenzie  Eric J. Sprigings 《Sports Engineering》2009,12(1):13-19

Theoretically, shaft stiffness can alter shot distance by increasing clubhead speed or altering clubhead orientation at impact. A 3D forward dynamics model of a golfer and flexible club simulated the downswing. A genetic algorithm optimized the coordination of the model’s muscles (four torque generators) to maximize clubhead speed. The maximum torque output and maximum rate of torque development from the torque generators were varied to simulate the swing of golfers that generate different clubhead speeds. Four shafts of varying stiffness (flexible, regular, stiff, and completely rigid) were entered into these simulations to examine the role that shaft flexibility had on clubhead speed and orientation at impact. Shaft stiffness was found to have a meaningful effect only on clubhead orientation (dynamic loft and dynamic close) at impact. There was no evidence to support the premise that matching the stiffness properties of the shaft with the golfer would improve clubhead speed.  相似文献