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61.
62.
Methoxycarbonyl groups in racemic biphenyls show separation of the methyl proton magnetic resonance signals in the presence of large amounts of chiral shift reagents.  相似文献   
63.
Furo[3,2-b]benzofuran was demonstrated to be an intermediate for the synthesis of dibenzofuran and 1,4-epoxy-1,4-dihydrodibenzofuran ring systems. Starting from the readily available aryl 3-bromomethyl-2-benzo[b]furyl ketones, a method was developed for the synthesis of 4-arylbenzofuro[2,3-d]pyridazines.  相似文献   
64.
An integrated CMOS high voltage supply for lab-on-a-chip systems   总被引:1,自引:0,他引:1  
Electrophoresis is a mainstay of lab-on-a-chip (LOC) implementations of molecular biology procedures and is the basis of many medical diagnostics. High voltage (HV) power supplies are necessary in electrophoresis instruments and are a significant part of the overall system cost. This cost of instrumentation is a significant impediment to making LOC technologies more widely available. We believe one approach to overcoming this problem is to use microelectronic technology (complementary metal-oxide semiconductor, CMOS) to generate and control the HV. We present a CMOS-based chip (3 mm x 2.9 mm) that generates high voltages (hundreds of volts), switches HV outputs, and is powered by a 5 V input supply (total power of 28 mW) while being controlled using a standard computer serial interface. Microchip electrophoresis with laser induced fluorescence (LIF) detection is implemented using this HV CMOS chip. With the other advancements made in the LOC community (e.g. micro-fluidic and optical devices), these CMOS chips may ultimately enable 'true' LOC solutions where essentially all the microfluidics, photonics and electronics are on a single chip.  相似文献   
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In this paper as the main result we prove that the projective special linear group L 16(2) is uniquely determined by its prime graph. In fact we give a positive answer to an open problem arose in Zavarnitsin (Algebra Logic 43(4), 220–231, 2006) and we obtain a first example of a finite group with connected prime graph which is uniquely determined by its prime graph. This research was in part supported by a grant from IPM (No. 86200023).  相似文献   
67.
Let G be a finite group. We define the prime graph Γ(G) as follows. The vertices of Γ(G) are the primes dividing the order of G and two distinct vertices p, q are joined by an edge if there is an element in G of order pq. Recently M. Hagie [5] determined finite groups G satisfying Γ(G) = Γ(S), where S is a sporadic simple group. Let p > 3 be a prime number. In this paper we determine finite groups G such that Γ(G) = Γ(PSL(2, p)). As a consequence of our results we prove that if p > 11 is a prime number and p ≢ 1 (mod 12), then PSL(2, p) is uniquely determined by its prime graph and so these groups are characterizable by their prime graph. The third author was supported in part by a grant from IPM (No. 84200024).  相似文献   
68.
In this paper we study the D-saturated property of bands defined in terms of their Cayley graphs Cay(S,C), where S is a band and C ? Z(S), the center of S. Also we characterize the Cayley graphs of bands. More generally, for a finite graph Γ =Cay(T, D), where T is a band and D ? Z(T), we give an algorithm for finding all bands S and C ? Z(S) such that Γ =Cay(S, C).  相似文献   
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Supply chains (SCs) can be managed at many levels. The use of tactical SC planning models with multiple flexibility options can help manage the usual operations efficiently and effectively, whilst improve the SC resiliency in response to inherent environmental uncertainties. This paper defines tactical SC flexibility and identifies tactical flexibility measures and options for development of flexible SC planning models. A classification of the existing literature of SC planning is introduced that highlights the characteristics of published flexibility inclusive models. Additional classifications from the reviewed literature are presented based on the integration of flexibility options used, solution methods utilized, and real world applications presented. These classifications are helpful for identifying research gaps in the current literature and provide insights for future modeling and research efforts in the field.  相似文献   
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