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Highly uniform ball-shaped indium bump arrays with small pixel pitches down to 10 μm have been fabricated. Multilayer stacked metal contact electrodes covered by a thin SiNx dielectric layer serve as the under bump metallization. Indium bumps were thermally evaporated inside the SiNx openings on top of the electrodes. Wet lift-off of the indium bumps was achieved by using a negative photoresist with precisely controlled undercuts. By comparison to a recipe without the SiNx, the non-uniform reflow effect of the indium materials was effectively eliminated after the thermal treatment. A mean indium ball diameter of 6.05 μm with a small coefficient of variation of 2.6% was finally realized for 10 μm pitch arrays. These results demonstrate the fabrication method is promising to ensure a reliable flip-chip hybridization of ultra-fine pitch focal plane arrays to silicon readout circuits with high yield.

High-precision measurement of X-ray spectra is affected by the statistical fluctuation of the X-ray beam under low-counting-rate conditions. It is also limited by counting loss resulting from the dead-time of the system and pile-up pulse effects, especially in a high-counting-rate environment. In this paper a detection system based on a FAST-SDD detector and a new kind of unit impulse pulse-shaping method is presented, for counting-loss correction in X-ray spectroscopy. The unit impulse pulse-shaping method is evolved by inverse deviation of the pulse from a reset-type preamplifier and a C-R shaper. It is applied to obtain the true incoming rate of the system based on a general fast–slow channel processing model. The pulses in the fast channel are shaped to unit impulse pulse shape which possesses small width and no undershoot. The counting rate in the fast channel is corrected by evaluating the dead-time of the fast channel before it is used to correct the counting loss in the slow channel.

The CR-(RC)n filter is used for Semi-Gaussian pulse shaping in analog spectroscopy. A new digital CR-(RC)n filter is presented based on the recursive models of the CR filter and RC filter. The spectroscopic signal reconstruction technique is proposed. This technique is applied to digital exponential decay signals obtained by the digitization of analog signals that represent the combined response of a FAST-SDD detector and the associated front-end circuit. Compared with the direct application of the digital CR-(RC)n filter, the technique eliminates the undershoot of the Semi-Gaussian pulse which is the primary cause of the low-energy peak tailing. And, the digital pole-zero cancellation filter follows digital CR-(RC)n filter to reduce the long tail of the shaped Semi-Gaussian pulse which leads to the high-energy peak tailing. Experimental results based on XRF signals of manganese sample show that the proposed techniques can cancel peak tailing due to the shaped Semi-Gaussian pulse improving FWTM/FWHM ratio and throughput capability.

This paper analyses first the state of water land exploitation and water saving irrigation in Xinjiang over the last 50 years. A fairly severe situation of water resources utilization exists in Xinjiang, and so agricultural water saving provides an important way of solving the problem. Taking a comprehensive view of development of agricultural irrigation in Xinjiang over the last 50 years, surface irrigation and new high water-saving technologies have both been present. Despite these two kinds of irrigation technologies, it is difficult to realize the effect of water saving and increasing production using the former, which is an engineering water-saving mode using a canal anti-seepage technique. To some degree, it inhibits ecological water use. The latter, which is an agronomic water-saving mode laying emphasis on crop growth mechanisms, can realize the effect of water saving and increasing production. But, on the other hand, it is unable to improve soil characteristics. On the contrary, it might even aggravate soil salinization. Therefore, both engineering water saving and agronomic water saving must reconsider the sustainability of water saving. Can it realize reasonable water resources allocation of the whole watershed? Can it realize sustainable utilization of water resources in the whole watershed? This paper advances a new concept of modern agricultural water saving – sustainable water saving – which is different from real water saving. Copyright © 2008 John Wiley & Sons, Ltd. Cet article analyse d'abord l'etat les conditions de la gestion de l'eau et des economies d'eau dans le Xinjiang au cours des 50 dernieres annees. La situation des ressources en eau au Xinjiang est severe, aussi l'economie d'eau en agriculture est une maniere importante de resoudre ce probleme grave. En considerant globalement le developpement de l'agriculture irriguee au Xinjiang depuis 50 ans, on voit coexister une irrigation de surface avec une irrigation nouvelle a haute technologie econome en eau. Bien qu'il y ait deux types de technologies d'irrigation, il est difficile de mesurer l'effet des economies d'eau et de la croissance de la production utilisant des techniques de lutte contre les fuites dans les canaux. A un certain point, les ecosystemes sont ainsi prives d'eau. La technologie recente qui est agronomique en utilisant le mecanisme de croissance des plantes, peut avoir un effet sur l'economie d'eau et la croissance de la production. Mais elle ne peut pas ameliorer les caracteristiques du sol. Au contraire il est meme possible d'aggraver la salinisation des sols. Par consequent, les methodes d'economie d'eau par le genie hydraulique ou par l'agronomie doivent reconsiderer leur durabilite. Peuvent-elles conduire a des allocations d'eau raisonnees sur tout le basin versant? Peuvent-elles assurer une utilisation durable des ressources d'eau? Ce papier developpe un nouveau concept d'economie en agriculture – l'economie durable – ce qui est different de l'economie reelle. Copyright © 2008 John Wiley & Sons, Ltd.

Studies show that aerobic exercise can significantly improve the functional status of the body and enhance the body resistance to diseases. There are controversial such as exercise time, period knowledge, movement pattern. We choose male colleges as an ordinary object and make body composition, blood as an indicator so that we research the effect on the lipid metabolism under the different aerobic running exercise program. We would have to find which kind of aerobic exercise program is good for the prevention and improvement lipid metabolism.

Energy resolution is affected by the intrinsic energy resolution of the detector, ballistic deficit, pileup pulses and noise. Pile-up pulses become the dominant factor that degrades energy resolution after the system is established, so pile-up rejection is often applied to obtain good energy resolution by discarding pulses that are expected to be contaminated by pile-up. However, pile-up rejection can reduce count rates and thus lower the measurement precision. In order to improve count rates and maintain energy resolution, a new method of pile-up pulse identification based on trapezoidal pulse shaping is presented. Combined with pulse width discrimination, this method is implemented by recording pulses that are not seriously piled up. Some experimental tests with a Cu-Pb alloy sample are carried out to verify the performance of this method in X-ray spectrometry. The results show that the method can significantly improve count rates without degrading energy resolution.更多还原