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Competing inhomogeneous orders are a central feature of correlated electron materials, including the high-temperature superconductors. The two-dimensional Hubbard model serves as the canonical microscopic physical model for such systems. Multiple orders have been proposed in the underdoped part of the phase diagram, which corresponds to a regime of maximum numerical difficulty. By combining the latest numerical methods in exhaustive simulations, we uncover the ordering in the underdoped ground state. We find a stripe order that has a highly compressible wavelength on an energy scale of a few kelvin, with wavelength fluctuations coupled to pairing order. The favored filled stripe order is different from that seen in real materials. Our results demonstrate the power of modern numerical methods to solve microscopic models, even in challenging settings.

Competing inhomogeneous orders are a central feature of correlated electron materials, including the high-temperature superconductors. The two-dimensional Hubbard model serves as the canonical microscopic physical model for such systems. Multiple orders have been proposed in the underdoped part of the phase diagram, which corresponds to a regime of maximum numerical difficulty. By combining the latest numerical methods in exhaustive simulations, we uncover the ordering in the underdoped ground state. We find a stripe order that has a highly compressible wavelength on an energy scale of a few kelvin, with wavelength fluctuations coupled to pairing order. The favored filled stripe order is different from that seen in real materials. Our results demonstrate the power of modern numerical methods to solve microscopic models, even in challenging settings.

Bichromophoric (4Z,15Z)-bilirubin-IXa, the cytotoxic and yel-: low-orange pigment of jaundice, prefers to adopt either of two enantiomeric intramolecularly hydrogeri-bonded conformations that are in dynamic equilibrium in solution. In the presence of optically active amino-alcohols, particularly ephedrines, the pigment solutions exhibit intense bisignate circular dichroism in the region of the bilirubin long wavelength UV-visible absorption band. The most intense circular dichroism Cotton effects, I !'lE; i --+ 200, are induced by O-methylephedrines, exceeding even those generally exhibited by bilirubin complexes with serum albumin and other proteins. Like serum albumin and other proteins, the optically active amino alcohols act as chiral templates, inducing an asymmetric transformation of bilirubin, whose induced bisignate circular dichroism Cotton effect originate from exciton sphtting of its two component pyrromethenone chromophores. The amines are thought to serve as agents for chiral molecular recognitlon by forming .diastereorneric salts with the pigment. And the complementary action of fJ-aryl and proximal hydroxyl and methoxyl group s provides insight into the binding forces important in bilirubinprotein binding.

Bichromophoric (4Z,15Z)-bilirubin-IXa, the cytotoxic and yel-: low-orange pigment of jaundice, prefers to adopt either of two enantiomeric intramolecularly hydrogeri-bonded conformations that are in dynamic equilibrium in solution. In the presence of optically active amino-alcohols, particularly ephedrines, the pigment solutions exhibit intense bisignate circular dichroism in the region of the bilirubin long wavelength UV-visible absorption band. The most intense circular dichroism Cotton effects, I !'lE; i --+ 200, are induced by O-methylephedrines, exceeding even those generally exhibited by bilirubin complexes with serum albumin and other proteins. Like serum albumin and other proteins, the optically active amino alcohols act as chiral templates, inducing an asymmetric transformation of bilirubin, whose induced bisignate circular dichroism Cotton effect originate from exciton sphtting of its two component pyrromethenone chromophores. The amines are thought to serve as agents for chiral molecular recognitlon by forming .diastereorneric salts with the pigment. And the complementary action of fJ-aryl and proximal hydroxyl and methoxyl group s provides insight into the binding forces important in bilirubinprotein binding.

The effect of process parameters was studied on the processing of a refractory Ni-Mo polymetallic ore grading 1.2% Ni and 1.61% Mo with 20.55% Fe, 11.7% S, 15.98% C and 20.45% SiO2. A Mo leaching rate of 95.67% was obtained by leaching under alkaline conditions using an oxidant dosage of 10 mol/l, a liquid/solid ratio of 3/1 and a leaching time of 2 h in a cold bath at 30 degrees C., The effect of process parameters was studied on the processing of a refractory Ni-Mo polymetallic ore grading 1.2% Ni and 1.61% Mo with 20.55% Fe, 11.7% S, 15.98% C and 20.45% SiO2. A Mo leaching rate of 95.67% was obtained by leaching under alkaline conditions using an oxidant dosage of 10 mol/l, a liquid/solid ratio of 3/1 and a leaching time of 2 h in a cold bath at 30 degrees C.