the science and politics of male infertility and sperm banking

... Following the suggestions of scientific literature on the advantages of the compactness, reliability, ease of use and affordability of the 980 nm Diode Lasers, we evaluated the efficacy and safety of ... are reduced [17,18] The lasers normally adopted offer the enormous advantage of being conveyed in a fibre, which serves as the working tip at the end of the handpiece The use of flexible, length-adjustable ... question the efficacy of the 980nm Laser for photosclerosis of lesions and areas with little melanin and hemoglobin pigmentation [7] Furthermore, to avoid exaggerated fluences and thermal damage to the...

Ngày tải lên: 26/10/2012, 09:48

... differently to these caps due to the short air pollutant lifetimes and dominance of northern over southern hemispheric emissions (Figs 4b and 4c) The northern hemisphere contributes the most to the global ... induced by the capping of SOx Note that these climate calculations in Figure omit the cooling effects of the CO2 reductions caused by the lessening of the inhibition of the land sink by ozone (Figure ... research was supported by the U.S Department of Energy, U.S National Science Foundation, and the Industry Sponsors of the MIT Joint Program on the Science and Policy of Global Change: Alstom Power...

Ngày tải lên: 17/02/2014, 22:20

... this planning the present monograph is entitled "The Science and Technology of Carbon Nanotubes" as the successive version of ref for the benefit of actual and potential researchers of these materials ... 1271 It would be of most importance to establish the controllability of the diameter and the helical pitch in this kind of synthesis of SWCNT toward the development of novel kinds of electronic ... to further improve the process of catalytic synthesis and, in order to so, clarification of the mechanism of CNT growth is necessary to control the synthesis CNT can be synthesized by the chemical...

Ngày tải lên: 05/03/2014, 17:20

... calling the first Idols of the Tribe, the second Idols of the Den, the third Idols of the Market, the fourth Idols of the Theatre 40 The information of notions and axioms on the foundation of true ... Arithmetic is the first of the sciences and the mother of safety.” BRANDEIS It is the aim of this little book to point the way to a new science and art the science and art of Human Engineering By ... disparity between the rapid progress of the natural and technological sciences on the one hand and the slow progress of the metaphysical, so-called social “sciences” on the other hand, that sooner...

Ngày tải lên: 22/03/2014, 23:20

... toxicities, and side effects of conventional treatment Quality of evidence of safety and efficacy of the CAM treatment Degree of understanding of the risks and benefits of conventional and CAM treatments ... at the patient’s X-ray or MRI image, while factors such as the candy bars and coffee consumed all day long, the computer work station, the stress of work and home, or the grief over the loss of ... the parenchyma of the liver, and lung and the nucleus pulposis The density of small-fiber distribution is not uniform throughout the tissue of the body, being greatest in the dermis and more scattered...

Ngày tải lên: 29/03/2014, 07:21

... the thrust to the foot of the cantilever tower, and the two sides of the towers balance each other The downward forces from the towers sit directly on and compress the foundations This idea of ... According to the latest theory the ‘critical number’ of people above which these wobbles will occur depends on the weight of the bridge, its natural frequency, and the amount of damping (i.e the degree ... lengths of rope and pieces of steel or other materials used in a real bridge to find out how strong they are The internal force is acting all along the length of the rope from one of the teams to the...

Ngày tải lên: 11/06/2014, 01:43

... importance One of the most striking examples is the difference in mass of two types of quarks, namely of the up and the down quark These two are the constituents of the proton and the neutron: the proton ... and electrons are orbiting around these nuclei The size of the atoms (the size of the outer orbit of the electrons) is of the order of 1/100 000 000 cm, the nucleus is 100 000 times smaller The ... considered to be the discoverer of the electron, in 1899, when he made a rough determination of the mass of the electron In those days one measured first the ratio of the charge and the mass of the particle...

Ngày tải lên: 11/06/2014, 10:16

... this planning the present monograph is entitled "The Science and Technology of Carbon Nanotubes" as the successive version of ref for the benefit of actual and potential researchers of these materials ... 1271 It would be of most importance to establish the controllability of the diameter and the helical pitch in this kind of synthesis of SWCNT toward the development of novel kinds of electronic ... to further improve the process of catalytic synthesis and, in order to so, clarification of the mechanism of CNT growth is necessary to control the synthesis CNT can be synthesized by the chemical...

Ngày tải lên: 27/06/2014, 17:20

... this planning the present monograph is entitled "The Science and Technology of Carbon Nanotubes" as the successive version of ref for the benefit of actual and potential researchers of these materials ... 1271 It would be of most importance to establish the controllability of the diameter and the helical pitch in this kind of synthesis of SWCNT toward the development of novel kinds of electronic ... to further improve the process of catalytic synthesis and, in order to so, clarification of the mechanism of CNT growth is necessary to control the synthesis CNT can be synthesized by the chemical...

Ngày tải lên: 27/06/2014, 18:20

... stroke: at the end of the intake stroke, both inlet and exhaust valves are closed The inertial action of the crankshaft in turn lifts the piston which compresses the mixture The ratio of the combustion ... openings in the bore wall The upward and downward motion of the piston simultaneously opens and closes these portholes The air-fuel mixture then goes in or out of the combustion chamber through the portholes ... rotation The combustion of the air-fuel mixture takes place in the chamber formed between the piston and the cylinder head The piston then moves up and down in the cylinder via combustion pressure and...

Ngày tải lên: 10/08/2014, 12:21

... between the piston and the cylinder bore is too narrow, then the expanded piston will touch the bore wall instantly If the clearance is too wide, it will cause blowby of the combustion gas when the ... 2.2, 2.27 and 2.40) The difference is in the shape of the coolant passages at the mating plane to the cylinder head The open deck type has a fully open coolant passage at the deck, whilst the closed ... should look not only at the surface, such as the hardness and the coefficient of friction, but also the quality of the substrate on which the modification is implemented The castings must have...

Ngày tải lên: 10/08/2014, 12:21

... follows the uneven shape of the cylinder bore wall Both the distorted cylinder and the swing motion of the piston make the ring gap open and close repeatedly During this motion, the degree of side ... into the clearance between the ring and ring groove The ring lifts in the groove with the inertial force during the exhaust cycle The piston ring 109 JIS-B8032 prescribes that the decline of the ... to break the ring A lack of lubrication also causes material failure The surface roughness of the ring groove and degree of groove and side 92 Science and technology of materials in automotive...

Ngày tải lên: 10/08/2014, 12:21

... Nomenclatures of the valve The shape from the crown to the neck is designed to give a smooth gas flow Figure 6.3 shows the position and relative motion of each part of the valve mechanism The motion of the ... at the solidification point The solidification temperature of cast iron is proportional to the sum of the percentage of carbon and one-third of the percentage of silicon This is known as the ... a product of the pressure (P) and relative slip speed (V) at the running surface, evaluating the severity of lubrication and friction conditions The higher the value, the more severe the working...

Ngày tải lên: 10/08/2014, 12:21

... for the valve and valve spring to follow the cam Valve float is the term given to unwanted movements of the valve and valve spring due to their inertial weights To avoid this, the load of the ... turn of the coil spring vibrates up and down at high frequency, independently of the motion of the entire spring It takes place when the natural frequency of the valve spring coincides with the ... other constructional steels chiefly in the degree of cold work, the higher carbon content, the fact that they can be supplied in the pre-tempered condition and their higher surface quality The...

Ngày tải lên: 10/08/2014, 12:21

... 8.10 Design of forging process The function of the forged part determines the required shape, material, accuracy and so on For the mechanical designer, the accuracy and strength of the part is ... rod (con-rod) and piston, to smooth revolutions The con-rod rides on the crankpin via a plain bearing The main bearing of the crankcase supports the main journal of the crankshaft The deep grooves ... at the surface because of the rapid cooling and the high carbon concentration on the surface The part does not undergo a martensitic transformation internally because of the slow cooling rate and...

Ngày tải lên: 10/08/2014, 12:21

... coil heats and austenitizes the surface, and then the part is quenched in water The depth of heating is related to the frequency of the alternating current; the higher the frequency, the thinner ... hardening25 of the crankpin and the corner radii between the crankpin and web The assembled crankshaft uses induction hardening of the hole into which the crankpin is forcefitted and of the corner ... stress Soft silver-plating protects the side surface of the retainer holding the rollers from side thrust The performance and life of bearings are very important in extending the life of the engine...

Ngày tải lên: 10/08/2014, 12:21

... prevent separation of the joint during operation, and so the bolt must be able to withstand the tightening load and the maximum inertial force To reduce the weight of the big end, the bolt hole should ... tend to separate the joint between the body and cap Even a slight separation increases friction loss at the big-end boss, and shortens the life of the plain bearing The stress on the con-rod bolt ... only to the shape of the big-end boss but also to the rigidity of the bolt itself The big-end boss should remain circular when the connecting rod bolts are tightened The mating planes in the joint...

Ngày tải lên: 10/08/2014, 12:21

... used The response and combustion efficiency of the wheel in acceleration is related to the inertial moment, a function of the weight The lower the weight, the lower the inertial moment and therefore ... the fuel and lubricant condense The quantity and composition of the particles depends on the combustion process, quality of diesel fuel and efficiency of after-treatment The soot is a solid and ... center of the housing The expanded engine exhaust gas is directed through the exhaust manifold into the turbine housing The exhaust gas pressure and the heat energy extracted from the gas cause the...

Ngày tải lên: 10/08/2014, 12:21

... at low cost The third column lists the means for meeting the requirements of each function, and the fourth column lists the properties required of the materials used The shape of the camshaft, ... Figure C.3 (c) shows the microstructure of a 0.8% carbon steel consisting of pearlite In the region of the mixture of α + γ, the amount of cementite 272 Science and technology of materials in automotive ... temperature of the water will rise until it is the same as that of the room This is the equilibrium state, and it will remain stable unless the temperature of the room is changed The phase diagram...

Ngày tải lên: 10/08/2014, 12:21

... dislocation cannot move through the grain boundary, and thus the metal is strengthened The smaller the grain size, the greater the number of dead ends, hence the stronger the iron Microstructural hardening: ... strain in solid solutions The radius of the white circle (atom) is different from that of the black circle.1 quarter of the tire size and these stones are densely dispersed, the driver has to take ... showing dislocations The distorted atomic arrangement of a dislocation scatters the transmitted electron beam, which causes the linear shadow in the photograph The misalignment of the atoms continues...

Ngày tải lên: 10/08/2014, 12:21